U.S. patent application number 14/110946 was filed with the patent office on 2014-01-30 for materials for electronic devices.
This patent application is currently assigned to Merck Patent GmbH Patents & Scientific Information. The applicant listed for this patent is Irina Martynova, Teresa Mujica-Fernaud, Christof Pflumm. Invention is credited to Irina Martynova, Teresa Mujica-Fernaud, Christof Pflumm.
Application Number | 20140027755 14/110946 |
Document ID | / |
Family ID | 45878899 |
Filed Date | 2014-01-30 |
United States Patent
Application |
20140027755 |
Kind Code |
A1 |
Mujica-Fernaud; Teresa ; et
al. |
January 30, 2014 |
MATERIALS FOR ELECTRONIC DEVICES
Abstract
The present invention relates to an electronic device comprising
one or more compounds of a formula (I) or (II). Furthermore, the
invention encompasses the use of a compound of the formula (I) or
(II) in an electronic device, and the provision of certain
compounds of the formula (I) or (II).
Inventors: |
Mujica-Fernaud; Teresa;
(Darmstadt, DE) ; Pflumm; Christof;
(Darmstadt-Arheilgen, DE) ; Martynova; Irina;
(Griesheim, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Mujica-Fernaud; Teresa
Pflumm; Christof
Martynova; Irina |
Darmstadt
Darmstadt-Arheilgen
Griesheim |
|
DE
DE
DE |
|
|
Assignee: |
Merck Patent GmbH Patents &
Scientific Information
Darmstadt
DE
|
Family ID: |
45878899 |
Appl. No.: |
14/110946 |
Filed: |
March 15, 2012 |
PCT Filed: |
March 15, 2012 |
PCT NO: |
PCT/EP2012/001156 |
371 Date: |
October 10, 2013 |
Current U.S.
Class: |
257/40 ; 252/500;
526/256; 526/257; 526/259; 544/180; 544/296; 544/333; 544/405;
546/104; 546/276.7; 546/70; 548/149; 548/223; 548/301.7; 548/305.1;
548/406; 548/414; 548/416; 548/418; 548/425 |
Current CPC
Class: |
C07D 471/14 20130101;
C07D 513/04 20130101; H01L 51/0072 20130101; H01L 51/0073 20130101;
H01L 51/0074 20130101; H01L 51/0035 20130101; C07D 519/00 20130101;
H01L 51/0094 20130101; Y02E 10/549 20130101; H01L 51/0071 20130101;
C07D 498/04 20130101; H01L 51/0067 20130101; C07D 487/22 20130101;
H01L 51/0085 20130101; C07D 487/04 20130101; H01L 51/5012 20130101;
H01L 51/0036 20130101 |
Class at
Publication: |
257/40 ; 252/500;
544/180; 548/425; 548/416; 544/333; 546/104; 548/418; 544/296;
544/405; 548/305.1; 548/414; 548/406; 546/276.7; 548/301.7;
548/149; 548/223; 546/70; 526/259; 526/256; 526/257 |
International
Class: |
H01L 51/00 20060101
H01L051/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 13, 2011 |
EP |
11003106.9 |
Claims
1-14. (canceled)
15. An electronic device, comprising an anode, a cathode and at
least one organic layer, wherein the organic layer comprises at
least one compound of the formula (I) or (II) ##STR00230## wherein:
Y is selected on each occurrence, identically or differently, from
BR.sup.0, C(R.sup.1).sub.2, Si(R.sup.1).sub.2, NR.sup.0, PR.sup.0,
P(.dbd.O)R.sup.0, O, S, S.dbd.O and S(.dbd.O).sub.2; Q, Z are on
each occurrence, identically or differently, CR.sup.1 or N; L is
selected from C.dbd.O, C.dbd.NR.sup.1, Si(R.sup.1).sub.2, NR.sup.1,
P(.dbd.O)(R.sup.1), O, S, SO, SO.sub.2, alkylene groups having 1 to
20 C atoms or alkenylene or alkynylene groups having 2 to 20 C
atoms, where one or more CH.sub.2 groups in the said groups may be
replaced by Si(R.sup.1).sub.2, O, S, C.dbd.O, C.dbd.NR.sup.1,
C(.dbd.O)O, (C.dbd.O)NR.sup.1, NR.sup.1, P(.dbd.O)(R.sup.1), SO or
SO.sub.2 and where one or more H atoms in the said groups may be
replaced by D, F, Cl, Br, I, CN or NO.sub.2, and aromatic or
heteroaromatic ring systems having 5 to 60 aromatic ring atoms,
which may in each case be substituted by one or more radicals
R.sup.1, and any desired combinations of 1, 2, 3, 4 or 5 identical
or different groups selected from the above-mentioned groups; or L
is a single bond, where p in this case is equal to 2; R.sup.0 is on
each occurrence, identically or differently, an aromatic or
heteroaromatic ring system having 5 to 60 aromatic ring atoms,
which may be substituted by one or more radicals R.sup.2, or an
aralkyl group or heteroaralkyl group having 5 to 60 aromatic ring
atoms, which may be substituted by one or more radicals R.sup.2;
R.sup.1 is on each occurrence, identically or differently, H, D, F,
Cl, Br, I, B(OR.sup.2).sub.2, CHO, C(.dbd.O)R.sup.2,
CR.sup.2.dbd.C(R.sup.2).sub.2, CN, C(.dbd.O)OR.sup.2,
C(.dbd.O)N(R.sup.2).sub.2, Si(R.sup.2).sub.3, N(R.sup.2).sub.2,
NO.sub.2, P(.dbd.O)(R.sup.2).sub.2, OSO.sub.2R.sup.2, OR.sup.2,
S(.dbd.O)R.sup.2, S(.dbd.O).sub.2R.sup.2, a straight-chain alkyl,
alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or
cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or
an alkenyl or alkynyl group having 2 to 20 C atoms, where the
above-mentioned groups may each be substituted by one or more
radicals R.sup.2 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.2C.dbd.CR.sup.2--, --C.ident.C--, Si(R.sup.2).sub.2,
Ge(R.sup.2).sub.2, Sn(R.sup.2).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.2, --C(.dbd.O)O--, --C(.dbd.O)NR.sup.2--, NR.sup.2,
P(.dbd.O)(R.sup.2), --O--, --S--, SO or SO.sub.2 and where one or
more H atoms in the above-mentioned groups may be replaced by D, F,
Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.2, or an aryloxy,
heteroaryloxy, aralkyl or heteroaralkyl group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.2, where two or more radicals R.sup.1 may be linked
to one another and may form a ring or a ring system; R.sup.2 is on
each occurrence, identically or differently, H, D, F, Cl, Br, I,
B(OR.sup.3).sub.2, CHO, C(.dbd.O)R.sup.3,
CR.sup.3.dbd.C(R.sup.3).sub.2, CN, C(.dbd.O)OR.sup.3,
C(.dbd.O)N(R.sup.3).sub.2, Si(R.sup.3).sub.3, N(R.sup.3).sub.2,
NO.sub.2, P(.dbd.O)(R.sup.3).sub.2, OSO.sub.2R.sup.3, OR.sup.3,
S(.dbd.O)R.sup.3, S(.dbd.O).sub.2R.sup.3, a straight-chain alkyl,
alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or
cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or
an alkenyl or alkynyl group having 2 to 20 C atoms, where the
above-mentioned groups may each be substituted by one or more
radicals R.sup.3 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.3C.dbd.CR.sup.3--, --C.ident.C--, Si(R.sup.3).sub.2,
Ge(R.sup.3).sub.2, Sn(R.sup.3).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.3, --C(.dbd.O)O--, --C(.dbd.O)NR.sup.3--, NR.sup.3,
P(.dbd.O)(R.sup.3), --O--, --S--, SO or SO.sub.2 and where one or
more H atoms in the above-mentioned groups may be replaced by D, F,
Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.3, or an aryloxy,
heteroaryloxy, aralkyl or heteroaralkyl group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.3, where two or more radicals R.sup.2 may be linked
to one another and may form a ring or a ring system; R.sup.3 is on
each occurrence, identically or differently, H, D, F or an
aliphatic, aromatic and/or heteroaromatic organic radical having 1
to 20 C atoms, in which, in addition, one or more H atoms may be
replaced by D or F; two or more substituents R.sup.3 here may also
be linked to one another and form a ring or a ring system; n is on
each occurrence, identically or differently, 0 or 1, where, in the
case n=0, the group in brackets is not present and optionally
groups R.sup.1 are instead bonded to the central benzene ring; P is
equal to 2, 3, 4, 5 or 6; and where the group Y and the nitrogen
atom at any desired adjacent positions may be bonded to the
aromatic six-membered ring; where, in the formulae (I) and (II), in
each case no or 1, 2 or 3 carbon atoms which are constituents of
the central aromatic six-membered ring may be replaced by N if the
sum of the indices n is equal to 0, and where, in the formulae (I)
and (II), in each case no or 1 or 2 carbon atoms which are
constituents of the central aromatic six-membered ring may be
replaced by N if the sum of the indices n is equal to 1, and where,
in formula (II), the moieties in square brackets with index p which
are bonded to L may be identical or different; and where, in
formula (II), the group L may be bonded at any desired position of
the moiety in square brackets with index p.
16. The electronic device according to claim 15, wherein p is equal
to 2.
17. The electronic device according to claim 15, wherein the sum of
the values for n in formula (I) and the sum of the values for n per
unit in square brackets with index p in formula (II) is equal to
0.
18. The electronic device according to claim 15, wherein 0 or 1
group Z per aromatic ring is equal to N.
19. The electronic device according to claim 15, wherein the group
Q is equal to CR.sup.1.
20. The electronic device according to claim 15, wherein the group
Y is selected on each occurrence, identically or differently, from
C(R.sup.1).sub.2, NR.sup.0, O and S.
21. The electronic device according to claim 15, wherein L is
selected from a single bond, where in this case p=2, or from
C.dbd.O, NR.sup.1, O or S, where in these cases p=2, or from
alkylene groups having 1 to 10 C atoms, alkenylene groups having 2
to 10 C atoms, where one or more CH.sub.2 groups in the said groups
may be replaced by C.dbd.O, NR.sup.1, P(.dbd.O)(R.sup.1), O or S,
and arylene or heteroarylene groups having 5 to 20 aromatic ring
atoms, which may be substituted by one or more radicals R.sup.1, or
from divalent aromatic or heteroaromatic ring systems of the
formula (L-1) * E .sub.i AR.sup.1 .sub.k E .sub.i Ar.sup.1 .sub.l E
.sub.i* formula (L-1) where p in this case is equal to 2 and
wherein: Ar.sup.1 is on each occurrence, identically or
differently, an aryl or heteroaryl group having 5 to 20 aromatic
ring atoms, which may in each case be substituted by one or more
radicals R.sup.1; E is on each occurrence, identically or
differently, a single bond, C.dbd.O, NAr.sup.1, P(.dbd.O)(R.sup.1),
O, S, SO or SO.sub.2; i is on each occurrence, identically or
differently, 0 or 1; k, l are on each occurrence, identically or
differently, 0, 1, 2 or 3, where the sum of the values of k and 1
is greater than 0; and where the groups Ar.sup.1 may be connected
to one another via one or more divalent groups T, where T is
selected on each occurrence, identically or differently, from a
single bond, BR.sup.1, C(R.sup.1).sub.2, C.dbd.O, C.dbd.S,
C.dbd.NR.sup.1, C.dbd.C(R.sup.1).sub.2, CR.sup.1.dbd.CR.sup.1,
Si(R.sup.1).sub.2, NR.sup.1, PR.sup.1, P(.dbd.O)R.sup.1, O, S,
S.dbd.O and S(.dbd.O).sub.2; and the symbols * mark bonds from the
group L to the remainder of the compound.
22. The electronic device according to claim 15, wherein the
compound of the formula (I) is selected from the formulae
##STR00231## ##STR00232## where the compounds may be substituted by
radicals R.sup.1 at all unsubstituted positions.
23. The electronic device according to claim 15, wherein the
compound of the formula (II) is selected from the formulae
##STR00233## ##STR00234## ##STR00235## ##STR00236## where the
symbols occurring are as defined in claim 15 and the group Z to
which the group L is bonded stands for a carbon atom, and where the
compounds may be substituted by radicals R.sup.1 at all
unsubstituted positions.
24. The electronic device according to claim 15, wherein the device
is selected from the group consisting of an organic integrated
circuit, an organic field-effect transistor, an organic thin-film
transistor, an organic light-emitting transistor, an organic solar
cell, an organic optical detector, an organic photoreceptor, an
organic field-quench device, a light-emitting electrochemical cell,
an organic laser diode, and an organic electroluminescent
device.
25. The electronic device according to claim 15, wherein the device
is an organic electroluminescent device, wherein the compound of
the formula (I) or (II) is present as hole-transport material in a
hole-transport layer or hole-injection layer and/or is present as
matrix material in an emitting layer and/or is present as
electron-transport material in an electron-transport layer.
26. A compound of the formula (I) or (II), ##STR00237## wherein: Y
is selected on each occurrence, identically or differently, from
BR.sup.0, C(R.sup.1).sub.2, Si(R.sup.1).sub.2, NR.sup.0, PR.sup.0,
P(.dbd.O)R.sup.0, O, S, S.dbd.O and S(.dbd.O).sub.2; Z are on each
occurrence, identically or differently, CR.sup.1 or N; Q is
CR.sup.1; L is selected from C.dbd.O, C.dbd.NR.sup.1,
Si(R.sup.1).sub.2, NR.sup.1, P(.dbd.O)(R.sup.1), O, S, SO,
SO.sub.2, alkylene groups having 1 to 20 C atoms or alkenylene or
alkynylene groups having 2 to 20 C atoms, where one or more
CH.sub.2 groups in the said groups may be replaced by
Si(R.sup.1).sub.2, O, S, C.dbd.O, C.dbd.NR.sup.1, C(.dbd.O)O,
(C.dbd.O)NR.sup.1, NR.sup.1, P(.dbd.O)(R.sup.1), SO or SO.sub.2 and
where one or more H atoms in the said groups may be replaced by D,
F, Cl, Br, I, CN or NO.sub.2, and aromatic or heteroaromatic ring
systems having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.1, and any desired
combinations of 1, 2, 3, 4 or 5 identical or different groups
selected from the above-mentioned groups; or L is a single bond,
where p in this case is equal to 2; R.sup.0 is on each occurrence,
identically or differently, an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may be substituted
by one or more radicals R.sup.2, or an aralkyl group or
heteroaralkyl group having 5 to 60 aromatic ring atoms, which may
be substituted by one or more radicals R.sup.2; R.sup.1 is on each
occurrence, identically or differently, H, D, F, Cl, Br, I,
B(OR.sup.2).sub.2, CHO, C(.dbd.O)R.sup.2,
CR.sup.2.dbd.C(R.sup.2).sub.2, CN, C(.dbd.O)OR.sup.2,
C(.dbd.O)N(R.sup.2).sub.2, Si(R.sup.2).sub.3, N(R.sup.2).sub.2,
NO.sub.2, P(.dbd.O)(R.sup.2).sub.2, OSO.sub.2R.sup.2, OR.sup.2,
S(.dbd.O)R.sup.2, S(.dbd.O).sub.2R.sup.2, a straight-chain alkyl,
alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or
cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or
an alkenyl or alkynyl group having 2 to 20 C atoms, where the
above-mentioned groups may each be substituted by one or more
radicals R.sup.2 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.2C.dbd.CR.sup.2--, --C.ident.C--, Si(R.sup.2).sub.2,
Ge(R.sup.2).sub.2, Sn(R.sup.2).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.2, --C(.dbd.O)O--, --C(.dbd.O)NR.sup.2--, NR.sup.2,
P(.dbd.O)(R.sup.2), --O--, --S--, SO or SO.sub.2 and where one or
more H atoms in the above-mentioned groups may be replaced by D, F,
Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.2, or an aryloxy,
heteroaryloxy, aralkyl or heteroaralkyl group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.2, where two or more radicals R.sup.1 may be linked
to one another and may form a ring or a ring system; R.sup.2 is on
each occurrence, identically or differently, H, D, F, Cl, Br, I,
B(OR.sup.3).sub.2, CHO, C(.dbd.O)R.sup.3,
CR.sup.3.dbd.C(R.sup.3).sub.2, CN, C(.dbd.O)OR.sup.3,
C(.dbd.O)N(R.sup.3).sub.2, Si(R.sup.3).sub.3, N(R.sup.3).sub.2,
NO.sub.2, P(.dbd.O)(R.sup.3).sub.2, OSO.sub.2R.sup.3, OR.sup.3,
S(.dbd.O)R.sup.3, S(.dbd.O).sub.2R.sup.3, a straight-chain alkyl,
alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or
cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or
an alkenyl or alkynyl group having 2 to 20 C atoms, where the
above-mentioned groups may each be substituted by one or more
radicals R.sup.3 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.3C.dbd.CR.sup.3--, --C.ident.C--, Si(R.sup.3).sub.2,
Ge(R.sup.3).sub.2, Sn(R.sup.3).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.3, --C(.dbd.O)O--, --C(.dbd.O)NR.sup.3--, NR.sup.3,
P(.dbd.O)(R.sup.3), --O--, --S--, SO or SO.sub.2 and where one or
more H atoms in the above-mentioned groups may be replaced by D, F,
Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.3, or an aryloxy,
heteroaryloxy, aralkyl or heteroaralkyl group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.3, where two or more radicals R.sup.2 may be linked
to one another and may form a ring or a ring system; R.sup.3 is on
each occurrence, identically or differently, H, D, F or an
aliphatic, aromatic and/or heteroaromatic organic radical having 1
to 20 C atoms, in which, in addition, one or more H atoms may be
replaced by D or F; two or more substituents R.sup.3 here may also
be linked to one another and form a ring or a ring system; n is on
each occurrence, identically or differently, 0 or 1, where, in the
case n=0, the group in brackets is not present and optionally
groups R.sup.1 are instead bonded to the central benzene ring; p is
equal to 2, 3, 4, 5 or 6; and where the group Y and the nitrogen
atom at any desired adjacent positions may be bonded to the
aromatic six-membered ring; where, in the formulae (I) and (II), in
each case no or 1, 2 or 3 carbon atoms which are constituents of
the central aromatic six-membered ring may be replaced by N if the
sum of the indices n is equal to 0, and where, in the formulae (I)
and (II), in each case no or 1 or 2 carbon atoms which are
constituents of the central aromatic six-membered ring may be
replaced by N if the sum of the indices n is equal to 1, and where,
in formula (II), the moieties in square brackets with index p which
are bonded to L may be identical or different; and where, in
formula (II), the group L may be bonded at any desired position of
the moiety in square brackets with index p; and the following
compounds are excluded: ##STR00238##
27. An oligomer, a polymer or a dendrimer comprising one or more
compound according to claim 26, wherein one or more bond to the
polymer, the oligomer or the dendrimer may be localised at any
positions in formula (I) or (II) that are substituted by R.sup.0 or
R.sup.1.
28. A formulation comprising at least one compound according to
claim 26 and at least one solvent.
29. A formulation comprising at least one polymer, oligomer or
dendrimer according to claim 27 and at least one solvent.
Description
[0001] The present invention relates to an electronic device
comprising one or more compounds of a formula (I) or (II) defined
below. Furthermore, the invention encompasses the use of a compound
of the formula (I) or (II) in an electronic device, and the
provision of certain compounds of the formula (I) or (II) defined
below.
[0002] The development of novel functional compounds for use in
electronic devices is currently the subject of intense research.
The aim here is the development and investigation of compounds
which have hitherto not yet been employed in electronic devices,
and the development of compounds which facilitate an improved
property profile of the devices.
[0003] The term electronic device in accordance with the present
invention is taken to mean, inter alia, organic integrated circuits
(OSCs), organic field-effect transistors (OLETs), organic thin-film
transistors (OTFTs), organic light-emitting transistors (OLETs),
organic solar cells (OSCs), organic optical detectors, organic
photoreceptors, organic field-quench devices (OFQDs), organic
light-emitting electrochemical cells (OLECs), organic laser diodes
(O-lasers) and organic electroluminescent devices (OLEDs).
[0004] The structure of organic electroluminescent devices (OLEDs)
in which the compounds of the formula (I) or (II) can preferably be
employed as functional materials is known to the person skilled in
the art and is described, inter alia, in U.S. Pat. No. 4,539,507,
U.S. Pat. No. 5,151,629, EP 0676461 and WO 1998/27136.
[0005] Further improvements are still necessary with respect to the
performance data of the organic electroluminescent devices, in
particular with a view to broad commercial use. Of particular
importance in this connection are the lifetime, the efficiency and
the operating voltage of the organic electroluminescent devices and
the colour values achieved. In particular in the case of
blue-emitting electroluminescent devices, there is potential for
improvement with respect to the lifetime of the devices.
[0006] In addition, it is desirable for the compounds for use as
organic semiconductor materials to have high thermal stability and
a high glass-transition temperature and to be sublimable without
decomposition.
[0007] In this connection, there is, inter alia, a demand for
alternative matrix materials for use in electronic devices. In
particular, there is a demand for matrix materials for
phosphorescent emitters which simultaneously result in good
efficiency, a long lifetime and a low operating voltage. It is
precisely the properties of the matrix materials that are
frequently limiting for the lifetime and efficiency of the organic
electroluminescent device.
[0008] In accordance with the prior art, carbazole derivatives, for
example bis(carbazolyl)biphenyl, are frequently used as matrix
materials. There is still potential for improvement here, in
particular with respect to the lifetime and glass-transition
temperature of the materials. Furthermore, there is a need for
improvement with respect to the operating voltage of the electronic
devices comprising the materials in question.
[0009] Furthermore, ketones (WO 2004/093207), phosphine oxides,
sulfones (WO 2005/003253) and triazine compounds, such as
triazinylspirobifluorene (cf. the applications WO 2005/053055 and
WO 2010/015306), are used as matrix materials for phosphorescent
emitters. There is still potential for improvement here, in
particular with respect to the efficiency and compatibility with
metal complexes which contain ketoketonate ligands, for example
acetylacetonate.
[0010] Furthermore, metal complexes, for example BAIq or zinc(II)
bis[2-(2-benzothiazole)phenolate], are used as matrix materials for
phosphorescent emitters. There is still a need for improvement
here, in particular with respect to the operating voltage and
chemical stability. Purely organic compounds are frequently more
stable than these metal complexes. Thus, some of these metal
complexes are sensitive to hydrolysis, which makes handling of the
complexes more difficult.
[0011] Also of particular interest is the provision of alternative
materials as matrix components of mixed-matrix systems. A
mixed-matrix system in the sense of this application is taken to
mean a system in which two or more different matrix compounds are
used mixed together with one (or more) dopant compounds as the
emitting layer. These systems are, in particular, of interest in
the case of phosphorescent organic electroluminescent devices. For
more detailed information, reference is made to the application WO
2010/108579. Compounds known from the prior art which may be
mentioned as matrix components in mixed-matrix systems are, inter
alia, CBP (biscarbazolylbiphenyl) and TCTA
(triscarbazolyltriphenylamine). However, there continues to be a
demand for alternative compounds for use as matrix components in
mixed-matrix systems. In particular, there is a demand for
compounds which effect an improvement in the operating voltage, the
power efficiency and the lifetime of the electronic devices.
[0012] Furthermore, there is a demand for alternative
hole-transport materials for use in electronic devices. In the case
of hole-transport materials in accordance with the prior art, the
voltage generally increases with the layer thickness of the
hole-transport layer. In practice, a greater layer thickness of the
hole-transport layer would frequently be desirable, but this often
has the consequence of a higher operating voltage and worse
performance data. In this connection, there is a demand for novel
hole-transport materials which have high charge-carrier mobility,
enabling thicker hole-transport layers to be achieved with only a
slight increase in the operating voltage.
[0013] The applications WO 2010/136109 and WO 2011/000455 disclose
indenocarbazole and indolocarbazole derivatives having different
linking geometry of the indene or indole and carbazole units. The
compounds are suitable for use as functional materials in organic
electroluminescent devices, in particular as matrix materials for
phosphorescent emitters and as electron-transport materials.
However, there continues to be a demand for alternative compounds,
in particular those by means of which a reduction in the operating
voltage, an increase in the power efficiency and an increase in the
lifetime can be achieved.
[0014] In the course of the present invention, it has been found
that compounds of the formula (I) or (II) indicated below are
highly suitable for use in electronic devices.
[0015] The present invention thus relates to an electronic device,
comprising anode, cathode and at least one organic layer, where the
organic layer comprises at least one compound of the formula (I) or
(II)
##STR00001##
where: [0016] Y is selected on each occurrence, identically or
differently, from BR.sup.0, C(R.sup.1).sub.2, Si(R.sup.1).sub.2,
NR.sup.0, PR.sup.0, P(.dbd.O)R.sup.0, O, S, S.dbd.O and
S(.dbd.O).sub.2; [0017] Q, Z are on each occurrence, identically or
differently, CR.sup.1 or N; [0018] L is selected from C.dbd.O,
C.dbd.NR.sup.1, Si(R.sup.1).sub.2, NR.sup.1, P(.dbd.O)(R.sup.1), O,
S, SO, SO.sub.2, alkylene groups having 1 to 20 C atoms or
alkynylene or alkynylene groups having 2 to 20 C atoms, where one
or more CH.sub.2 groups in the said groups may be replaced by
Si(R.sup.1).sub.2, O, S, C.dbd.O, C.dbd.NR.sup.1, C(.dbd.O)O,
(C.dbd.O)NR.sup.1, NR.sup.1, P(.dbd.O)(R.sup.1), SO or SO.sub.2 and
where one or more H atoms in the said groups may be replaced by D,
F, Cl, Br, I, CN or NO.sub.2, and aromatic or heteroaromatic ring
systems having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.1, and any desired
combinations of 1, 2, 3, 4 or 5 identical or different groups
selected from the above-mentioned groups; or L is a single bond,
where p in this case is equal to 2; [0019] R.sup.0 is on each
occurrence, identically or differently, an aromatic or
heteroaromatic ring system having 5 to 60 aromatic ring atoms,
which may be substituted by one or more radicals R.sup.2, or an
aralkyl group or heteroaralkyl group having 5 to 60 aromatic ring
atoms, which may be substituted by one or more radicals R.sup.2;
[0020] R.sup.1 is on each occurrence, identically or differently,
H, D, F, Cl, Br, I, B(OR.sup.2).sub.2, CHO, C(.dbd.O)R.sup.2,
CR.sup.2.dbd.C(R.sup.2).sub.2, CN, C(.dbd.O)OR.sup.2,
C(.dbd.O)N(R.sup.2).sub.2, Si(R.sup.2).sub.3, N(R.sup.2).sub.2,
NO.sub.2, P(.dbd.O)(R.sup.2).sub.2, OSO.sub.2R.sup.2, OR.sup.2,
S(.dbd.O)R.sup.2, S(.dbd.O).sub.2R.sup.2, a straight-chain alkyl,
alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or
cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or
an alkenyl or alkynyl group having 2 to 20 C atoms, where the
above-mentioned groups may each be substituted by one or more
radicals R.sup.2 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.2C.dbd.CR.sup.2--, --C.ident.C--, Si(R.sup.2).sub.2,
Ge(R.sup.2).sub.2, Sn(R.sup.2).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.2, --C(.dbd.O)O--, --C(.dbd.O)NR.sup.2--, NR.sup.2,
P(.dbd.O)(R.sup.2), --O--, --S--, SO or SO.sub.2 and where one or
more H atoms in the above-mentioned groups may be replaced by D, F,
Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.2, or an aryloxy,
heteroaryloxy, aralkyl or heteroaralkyl group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.2, where two or more radicals R.sup.1 may be linked
to one another and may form a ring or a ring system; [0021] R.sup.2
is on each occurrence, identically or differently, H, D, F, Cl, Br,
I, B(OR.sup.3).sub.2, CHO, C(.dbd.O)R.sup.3,
CR.sup.3.dbd.C(R.sup.3).sub.2, CN, C(.dbd.O)OR.sup.3,
C(.dbd.O)N(R.sup.3).sub.2, Si(R.sup.3).sub.3, N(R.sup.3).sub.2,
NO.sub.2, P(.dbd.O)(R.sup.3).sub.2, OSO.sub.2R.sup.3, OR.sup.3,
S(.dbd.O)R.sup.3, S(.dbd.O).sub.2R.sup.3, a straight-chain alkyl,
alkoxy or thioalkyl group having 1 to 20 C atoms or a branched or
cyclic alkyl, alkoxy or thioalkyl group having 3 to 20 C atoms or
an alkenyl or alkynyl group having 2 to 20 C atoms, where the
above-mentioned groups may each be substituted by one or more
radicals R.sup.3 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.3C.dbd.CR.sup.3--, --C.ident.C--, Si(R.sup.3).sub.2,
Ge(R.sup.3).sub.2, Sn(R.sup.3).sub.2, C.dbd.O, C.dbd.S, C.dbd.Se,
C.dbd.NR.sup.3, --C(.dbd.O)O--, --C(.dbd.O)NR.sup.3--, NR.sup.3,
P(.dbd.O)(R.sup.3), --O--, --S--, SO or SO.sub.2 and where one or
more H atoms in the above-mentioned groups may be replaced by D, F,
Cl, Br, I, CN or NO.sub.2, or an aromatic or heteroaromatic ring
system having 5 to 60 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.3, or an aryloxy,
heteroaryloxy, aralkyl or heteroaralkyl group having 5 to 60
aromatic ring atoms, which may be substituted by one or more
radicals R.sup.3, where two or more radicals R.sup.2 may be linked
to one another and may form a ring or a ring system; [0022] R.sup.3
is on each occurrence, identically or differently, H, D, F or an
aliphatic, aromatic and/or heteroaromatic organic radical having 1
to 20 C atoms, in which, in addition, one or more H atoms may be
replaced by D or F; two or more substituents R.sup.3 here may also
be linked to one another and form a ring or a ring system; [0023] n
is on each occurrence, identically or differently, 0 or 1, where,
in the case n=0, the group in brackets is not present and
optionally groups R.sup.1 are instead bonded to the central benzene
ring; [0024] p is equal to 2, 3, 4, 5 or 6; and where the group Y
and the nitrogen atom at any desired adjacent positions may be
bonded to the aromatic six-membered ring; where, in the formulae
(I) and (II), in each case no or 1, 2 or 3 carbon atoms which are
constituents of the central aromatic six-membered ring may be
replaced by N if the sum of the indices n is equal to 0, and where,
in the formulae (I) and (II), in each case no or 1 or 2 carbon
atoms which are constituents of the central aromatic six-membered
ring may be replaced by N if the sum of the indices n is equal to
1, and where, in formula (II), the moieties in square brackets with
index p which are bonded to L may be identical or different; and
where, in formula (II), the group L may be bonded at any desired
position of the moiety in square brackets with index p.
[0025] An aryl group in the sense of this invention contains 6 to
60 aromatic ring atoms; a heteroaryl group in the sense of this
invention contains 1 to 60 C atoms at least one heteroatom, with
the proviso that the sum of C atoms and heteratoms is at least 5.
The heteroatoms are preferably selected from N, O and/or S.
[0026] An aryl group or heteroaryl group here is taken to mean
either a simple aromatic ring, i.e. benzene, or a simple
heteroaromatic ring, for example pyridine, pyrimidine or thiophene,
or a condensed (annellated) aromatic or heteroaromatic polycycle,
for example naphthalene, phenanthrene, quinoline or carbazole. A
condensed (annellated) aromatic or heteroaromatic polycycle in the
sense of the present application consists of two or more simple
aromatic or heteroaromatic rings condensed with one another.
[0027] An aryl or heteroaryl group, which may in each case be
substituted by the above-mentioned radicals and which may be linked
to the aromatic or heteroaromatic ring system via any desired
positions, is taken to mean, in particular, groups derived from
benzene, naphthalene, anthracene, phenanthrene, pyrene,
dihydropyrene, chrysene, perylene, fluoranthene, benzanthracene,
benzophenanthrene, tetracene, pentacene, benzopyrene, furan,
benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene,
isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole,
carbazole, pyridine, quinoline, isoquinoline, acridine,
phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline,
benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole,
indazole, imidazole, benzimidazole, naphthimidazole,
phenanthrimidazole, pyridimidazole, pyrazinimidazole,
quinoxalinimidazole, oxazole, benzoxazole, naphthoxazole,
anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole,
1,3-thiazole, benzothiazole, pyridazine, benzopyridazine,
pyrimidine, benzopyrimidine, quinoxaline, pyrazine, phenazine,
naphthyridine, azacarbazole, benzocarboline, phenanthroline,
1,2,3-triazole, 1,2,4-triazole, benzotriazole, 1,2,3-oxadiazole,
1,2,4-oxadiazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole,
1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole,
1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine,
tetrazole, 1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine,
purine, pteridine, indolizine and benzothiadiazole.
[0028] An aralkyl group in the sense of this invention is an alkyl
group which is substituted by an aryl group, where the term aryl
group is to be understood as defined above and the alkyl group has
1 to 20 C atoms, where individual H atoms and/or CH.sub.2 groups in
the alkyl group may also be replaced by the groups mentioned above
under the definition of R.sup.1 and R.sup.2 and where the alkyl
group represents the group which is bonded to the remainder of the
compound. Correspondingly, a heteroaralkyl group represents an
alkyl group which is substituted by a heteroaryl group, where the
term heteroaryl group is to be understood as defined above and the
alkyl group has 1 to 20 C atoms, where individual H atoms and/or
CH.sub.2 groups in the alkyl group may also be replaced by the
groups mentioned above under the definition of R.sup.1 and R.sup.2
and where the alkyl group represents the group which is bonded to
the remainder of the compound.
[0029] An aromatic ring system in the sense of this invention
contains 6 to 60 C atoms in the ring system. A heteroaromatic ring
system in the sense of this invention contains 5 to 60 aromatic
ring atoms, at least one of which is a heteroatom. The heteroatoms
are preferably selected from N, O and/or S. An aromatic or
heteroaromatic ring system in the sense of this invention is
intended to be taken to mean a system which does not necessarily
contain only aryl or heteroaryl groups, but instead in which, in
addition, a plurality of aryl or heteroaryl groups may be connected
by a non-aromatic unit (preferably less than 10% of the atoms other
than H), such as, for example, an sp.sup.3-hybridised C, Si, N or O
atom, an sp.sup.2-hybridised C or N atom or an sp-hybridised C
atom. Thus, for example, systems such as 9,9'-spirobifluorene,
9,9'-diarylfluorene, triarylamine, diaryl ether, stilbene, etc.,
are also intended to be taken to be aromatic ring systems in the
sense of this invention, as are systems in which two or more aryl
groups are connected, for example, by a linear or cyclic alkyl,
alkenyl or alkynyl group or by a silyl group. Furthermore, systems
in which two or more aryl or heteroaryl groups are linked to one
another via single bonds are also taken to be aromatic or
heteroaromatic ring systems in the sense of this invention, such
as, for example, systems such as biphenyl, terphenyl or
diphenyltriazine.
[0030] An aromatic or heteroaromatic ring system having 5-60
aromatic ring atoms, which may in each case also be substituted by
radicals as defined above and which may be linked to the aromatic
or heteroaromatic group via any desired positions, is taken to
mean, in particular, groups derived from benzene, naphthalene,
anthracene, benzanthracene, phenanthrene, benzophenanthrene,
pyrene, chrysene, perylene, fluoranthene, naphthacene, pentacene,
benzopyrene, biphenyl, biphenylene, terphenyl, terphenylene,
quaterphenyl, fluorene, spirobifluorene, dihydrophenanthrene,
dihydropyrene, tetrahydropyrene, cis- or trans-indenofluorene,
truxene, isotruxene, spirotruxene, spiroisotruxene, furan,
benzofuran, isobenzofuran, dibenzofuran, thiophene, benzothiophene,
isobenzothiophene, dibenzothiophene, pyrrole, indole, isoindole,
carbazole, indolocarbazole, indenocarbazole, pyridine, quinoline,
isoquinoline, acridine, phenanthridine, benzo-5,6-quinoline,
benzo-6,7-quinoline, benzo-7,8-quinoline, phenothiazine,
phenoxazine, pyrazole, indazole, imidazole, benzimidazole,
naphthimidazole, phenanthrimidazole, pyridimidazole,
pyrazinimidazole, quinoxalinimidazole, oxazole, benzoxazole,
naphthoxazole, anthroxazole, phenanthroxazole, isoxazole,
1,2-thiazole, 1,3-thiazole, benzothiazole, pyridazine,
benzopyridazine, pyrimidine, benzopyrimidine, quinoxaline,
1,5-diazaanthracene, 2,7-diazapyrene, 2,3-diazapyrene,
1,6-diazapyrene, 1,8-diazapyrene, 4,5-diazapyrene,
4,5,9,10-tetraazaperylene, pyrazine, phenazine, phenoxazine,
phenothiazine, fluorubin, naphthyridine, azacarbazole,
benzocarboline, phenanthroline, 1,2,3-triazole, 1,2,4-triazole,
benzotriazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole,
1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-thiadiazole,
1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thiadiazole,
1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, tetrazole,
1,2,4,5-tetrazine, 1,2,3,4-tetrazine, 1,2,3,5-tetrazine, purine,
pteridine, indolizine and benzothiadiazole, or combinations of
these groups.
[0031] For the purposes of the present invention, a straight-chain
alkyl group having 1 to 40 C atoms or a branched or cyclic alkyl
group having 3 to 40 C atoms or an alkenyl or alkynyl group having
2 to 40 C atoms, in which, in addition, individual H atoms or
CH.sub.2 groups may be substituted by the groups mentioned above
under the definition of the radicals, is preferably taken to mean
the radicals methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl,
s-butyl, t-butyl, 2-methylbutyl, n-pentyl, s-pentyl, cyclopentyl,
neopentyl, n-hexyl, cyclohexyl, neohexyl, n-heptyl, cycloheptyl,
n-octyl, cyclooctyl, 2-ethylhexyl, trifluoromethyl,
pentafluoroethyl, 2,2,2-trifluoroethyl, ethenyl, propenyl, butenyl,
pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, heptenyl,
cycloheptenyl, octenyl, cyclooctenyl, ethynyl, propynyl, butynyl,
pentynyl, hexynyl or octynyl. An alkoxy or thioalkyl group having 1
to 40 C atoms is preferably taken to mean methoxy,
trifluoromethoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy,
s-butoxy, t-butoxy, n-pentoxy, s-pentoxy, 2-methylbutoxy, n-hexoxy,
cyclohexyloxy, n-heptoxy, cycloheptyloxy, n-octyloxy,
cyclooctyloxy, 2-ethylhexyloxy, pentafluoroethoxy,
2,2,2-trifluoroethoxy, methylthio, ethylthio, n-propylthio,
i-propylthio, n-butylthio, i-butylthio, s-butylthio, t-butylthio,
n-pentylthio, s-pentylthio, n-hexylthio, cyclohexylthio,
n-heptylthio, cycloheptylthio, n-octylthio, cyclooctylthio,
2-ethylhexylthio, trifluoromethylthio, pentafluoroethylthio,
2,2,2-trifluoroethylthio, ethenylthio, propenylthio, butenylthio,
pentenylthio, cyclopentenylthio, hexenylthio, cyclohexenylthio,
heptenylthio, cycloheptenylthio, octenylthio, cyclooctenylthio,
ethynylthio, propynylthio, butynylthio, pentynylthio, hexynylthio,
heptynylthio or octynylthio.
[0032] The formulation that two or more radicals may form a ring
with one another is, the purposes of the present description,
intended to be taken to mean, inter alia, that the two radicals are
linked to one another by a chemical bond. This is illustrated by
the following scheme:
##STR00002##
[0033] Furthermore, however, the above-mentioned formulation is
also intended to be taken to mean that, in the case where one of
the two radicals represents hydrogen, the second radical is bonded
at the position to which the hydrogen atom was bonded, with
formation of a ring. This is intended to be illustrated by the
following scheme:
##STR00003##
[0034] Furthermore, it should be emphasised that the bonds starting
from N and Y drawn into the central benzene ring may emanate from
any desired free position of the benzene. However, these must be
adjacent positions, as indicated above in the definition of the
compounds according to the invention.
[0035] It is not intended to be derived from the type of depiction
in formula (I) and formula (II) that N must be bonded to the
benzene ring above Y. The spatial arrangement of the indole
derivative with the bridge Y can therefore be selected freely
within the scope of the invention, so long as N and the group Y are
bonded in adjacent positions.
[0036] Preferred embodiments for the bonding positions of Y and N
are revealed by the preferred structures of compounds of the
formula (I) or (II) depicted in a following section.
[0037] In accordance with the invention, the group L in compounds
of the formula (II) can be bonded at any desired position of the
moiety in square brackets with index p. The bonding preferably
takes place to identical positions, i.e. symmetrically. The bonding
furthermore preferably takes place via the positions marked with a
circle below in the following formula (II), where, in the case of
bonding via the central benzene ring, a maximum of one of the two
indices n may be equal to 1.
[0038] Alternatively, bonding of L may also take place via a group
Y.
##STR00004##
[0039] Preferred embodiments of formula (II) thus conform to the
formulae (II-A) to (II-C)
##STR00005##
where, in formula (II-A), the group Z to which the group L is
bonded stands for a carbon atom.
[0040] According to a further preferred embodiment, the moieties in
square brackets with index p which are bonded to L in formula (II)
are selected identically, i.e. the compound is symmetrical.
[0041] Furthermore, the index p, which indicates the number of
moieties bonded to L, is preferably equal to 2 or 3 and
particularly preferably equal to 2.
[0042] According to a preferred embodiment, the sum of the values
for n in formula (I) is equal to 0 or 1, it is particularly
preferably equal to 0. According to a preferred embodiment, the sum
of the values for n per unit in square brackets with index p for
formula (II) is equal to 0 or 1, particularly preferably equal to
0.
[0043] For the group Z, this is generally preferably equal to
CR.sup.1. Furthermore preferably, not more than 2 adjacent groups Z
are equal to N. Furthermore preferably, 0, 1, 2 or 3, particularly
preferably 0, 1 or 2, and very particularly preferably 0 or 1, Z
per aromatic ring is equal to N.
[0044] It is furthermore preferred for the group Q to be equal to
CR.sup.1.
[0045] For the group Y, this is preferably selected on each
occurrence, identically or differently, from C(R.sup.1).sub.2,
NR.sup.0, O and S, particularly preferably from C(R.sup.1).sub.2
and NR.sup.0 and very particularly preferably from
C(R.sup.1).sub.2.
[0046] L is preferably selected from a single bond, where in this
case p=2.
[0047] L is likewise preferably selected from C.dbd.O, NR.sup.1, O
or S, where in these cases p=2, or from alkylene groups having 1 to
10 C atoms, alkenylene groups having 2 to 10 C atoms, where one or
more CH.sub.2 groups in the said groups may be replaced by C.dbd.O,
NR.sup.1, P(.dbd.O)(R.sup.1), O or S, or from arylene or
heteroarylene groups having 5 to 20 aromatic ring atoms, which may
be substituted by one or more radicals R.sup.1. The index p in
these cases is preferably equal to 2, but may also be larger, for
example 3.
[0048] L is likewise preferably a divalent aromatic or
heteroaromatic ring system of the formula (L-1) formula (L-1),
* E .sub.i AR.sup.1 .sub.k E .sub.i Ar.sup.1 .sub.l E .sub.i*
formula (L-1)
where p in this case is equal to 2 and where furthermore: [0049]
Ar.sup.1 is on each occurrence, identically or differently, an aryl
or heteroaryl group having 5 to 20 aromatic ring atoms, which may
in each case be substituted by one or more radicals R.sup.1; [0050]
E is on each occurrence, identically or differently, a single bond,
C.dbd.O, NAr.sup.1, P(.dbd.O)(R.sup.1), O, S, SO or SO.sub.2;
[0051] i is on each occurrence, identically or differently, 0 or 1;
[0052] k, l are on each occurrence, identically or differently, 0,
1, 2 or 3, where the sum of the values of k and I is greater than
0; and where furthermore the groups Ar.sup.1 may be connected to
one another via one or more divalent groups T, where [0053] T is
selected on each occurrence, identically or differently, from a
single bond, BR.sup.1, C(R.sup.1).sub.2, C.dbd.O, C.dbd.S,
C.dbd.NR.sup.1, C.dbd.C(R.sup.1).sub.2, CR.sup.1.dbd.CR.sup.1,
Si(R.sup.1).sub.2, NR.sup.1, PR.sup.1, P(.dbd.O)R.sup.1, O, S,
S.dbd.O and S(.dbd.O).sub.2; and the symbols * mark bonds from the
group L to the remainder of the compound. L is particularly
preferably a single bond or an arylene or heteroarylene group
having 5 to 18 aromatic ring atoms, which may be substituted by one
or more radicals R.sup.1, or a divalent aromatic or heteroaromatic
ring system of the formula (L-1), where the index p is equal to 2
and where, restricting the definitions indicated above for formula
(L-1), [0054] E is on each occurrence, identically or differently,
a single bond, C.dbd.O, NAr.sup.1, O or S; [0055] k, l is on each
occurrence, identically or differently, 0 or 1, where the sum of
the values of k and l is greater than 0; and [0056] T is selected
on each occurrence, identically or differently, from a single bond,
C(R.sup.1).sub.2, C.dbd.O, NR.sup.1, O and S.
[0057] Furthermore preferably, [0058] R.sup.0 is on each
occurrence, identically or differently, an aromatic or
heteroaromatic ring system having 5 to 30 aromatic ring atoms,
which may be substituted by one or more radicals R.sup.2.
[0059] Particularly preferably, [0060] R.sup.0 is on each
occurrence, identically or differently, an aryl or heteroaryl group
having 5 to 20 aromatic ring atoms, which may be substituted by one
or more radicals R.sup.2.
[0061] Very particularly preferably, [0062] R.sup.0 is selected on
each occurrence, identically or differently, from phenyl, naphthyl,
pyridyl, pyrimidyl, pyrazinyl or triazinyl, which may be
substituted by one or more radicals R.sup.2.
[0063] Preferably, [0064] R.sup.1 is selected on each occurrence,
identically or differently, from H, D, F, CN, Si(R.sup.2).sub.3,
N(R.sup.2).sub.2 or a straight-chain alkyl or alkoxy group having 1
to 20 C atoms or a branched or cyclic alkyl or alkoxy group having
3 to 20 C atoms, where the above-mentioned groups may each be
substituted by one or more radicals R.sup.2 and where one or more
CH.sub.2 groups in the above-mentioned groups may be replaced by
--C.ident.C--, --R.sup.2C.dbd.CR.sup.2--, Si(R.sup.2).sub.2,
C.dbd.O, C.dbd.NR.sup.2, --NR.sup.2--, --O--, --S--, --C(.dbd.O)O--
or --C(.dbd.O)NR.sup.2--, or an aromatic or heteroaromatic ring
system having 5 to 20 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.2, where two or more
radicals R.sup.1 may be linked to one another and may form a ring
or a ring system.
[0065] Particularly preferably, [0066] R.sup.1 is selected on each
occurrence, identically or differently, from H, D, F,
N(R.sup.2).sub.2, a straight-chain alkyl group having 1 to 8 C
atoms or a branched or cyclic alkyl group having 3 to 8 C atoms,
where the above-mentioned groups may each be substituted by one or
more radicals R.sup.2 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.2C.dbd.CR.sup.2--, --NR.sup.2--, --O-- or --S--, or an aryl
or heteroaryl group having 5 to 20 aromatic ring atoms, which may
in each case be substituted by one or more radicals R.sup.2.
[0067] Preferably, [0068] R.sup.2 is selected on each occurrence,
identically or differently, from H, D, F, CN, Si(R.sup.3).sub.3,
N(R.sup.3).sub.2 or a straight-chain alkyl or alkoxy group having 1
to 20 C atoms or a branched or cyclic alkyl or alkoxy group having
3 to 20 C atoms, where the above-mentioned groups may each be
substituted by one or more radicals R.sup.3 and where one or more
CH.sub.2 groups in the above-mentioned groups may be replaced by
--C.ident.C--, --R.sup.3C.dbd.CR.sup.3--, Si(R.sup.3).sub.2,
C.dbd.O, C.dbd.NR.sup.3, --NR.sup.3--, --O--, --S--, --C(.dbd.O)O--
or --C(.dbd.O)NR.sup.3--, or an aromatic or heteroaromatic ring
system having 5 to 20 aromatic ring atoms, which may in each case
be substituted by one or more radicals R.sup.3, where two or more
radicals R.sup.2 may be linked to one another and may form a ring
or a ring system.
[0069] Particularly preferably, [0070] R.sup.2 is selected on each
occurrence, identically or differently, from H, D, F,
N(R.sup.3).sub.2, a straight-chain alkyl group having 1 to 8 C
atoms or a branched or cyclic alkyl group having 3 to 8 C atoms,
where the above-mentioned groups may each be substituted by one or
more radicals R.sup.3 and where one or more CH.sub.2 groups in the
above-mentioned groups may be replaced by
--R.sup.3C.dbd.CR.sup.3--, --NR.sup.3--, --O-- or --S--, or an aryl
or heteroaryl group having 5 to 20 aromatic ring atoms, which may
in each case be substituted by one or more radicals R.sup.3.
[0071] It is furthermore preferred for the compounds according to
the invention to carry, as substituent R.sup.1, at least one group
selected from groups R.sup.1-I, R.sup.1-II and R.sup.1-III, for
which: [0072] R.sup.1-I is a heteroaryl group having 5 to 20
aromatic ring atoms or a keto group or a phosphorus oxide group or
a sulfur oxide group, each of which is bonded directly or via one
or more divalent aryl or heteroaryl groups and which may be
substituted by one or more radicals R.sup.2; [0073] R.sup.1-II is
an aromatic or heteroaromatic ring system having 5 to 24 aromatic
ring atoms, which may be substituted by one or more radicals
R.sup.2, and [0074] R.sup.1-III is an arylamine group, which may be
substituted by one or more radicals R.sup.2.
[0075] A keto group which is bonded directly or via one or more
divalent aryl groups and which may be substituted by a radical
R.sup.2 is for the purposes of the present invention taken to mean
a group of the following formula
##STR00006##
where the dashed bond represents the bonding site of the keto
group, [0076] q can be equal to 0, 1, 2, 3, 4 or 5, [0077] Ar.sup.2
represents on each occurrence, identically or differently, an aryl
or heteroaryl group having 5 to 20 aromatic ring atoms, which may
be substituted by one or more radicals R.sup.2, where the groups
Ar.sup.2 may be connected to one another via one or more groups U;
and [0078] U is selected on each occurrence, identically or
differently, from a single bond, BR.sup.2, C(R.sup.2).sub.2,
C.dbd.O, C.dbd.S, C.dbd.NR.sup.2, C.dbd.C(R.sup.2).sub.2,
CR.sup.2.dbd.CR.sup.2, Si(R.sup.2).sub.2, NR.sup.2, PR.sup.2,
P(.dbd.O)R.sup.2, O, S, S.dbd.O and S(.dbd.O).sub.2; and [0079]
R.sup.2 is as defined above.
[0080] A phosphorus oxide group which is bonded directly or via one
or more divalent aryl groups and which may be substituted by a
radical R.sup.2 is for the purposes of the present invention taken
to mean a group of the following formula
##STR00007##
where the dashed bond represents the bonding site of the phosphorus
oxide group and R.sup.2, q and Ar.sup.2 are as defined above, where
the groups Ar.sup.2 may be connected to one another via one or more
groups U, as defined above.
[0081] A sulfur oxide group which is bonded directly or via one or
more divalent aryl groups and which may be substituted by a radical
R.sup.2 is for the purposes of the present invention taken to mean
a group of the following formula
##STR00008##
where the dashed bond represents the bonding site of the sulfur
oxide group, a can be equal to 1 or 2, and R.sup.2, q and Ar.sup.2
are as defined above, where the groups Ar.sup.2 may be connected to
one another via one or more groups U, as defined above.
[0082] The above-mentioned groups R.sup.1-I preferably represent
groups of the following formula
HetAr.sup.1 Ar.sup.2 .sub.q*
where the symbol * marks the bond to the remainder of the compound
and furthermore q and Ar.sup.2 are as defined above, where the
groups Ar.sup.2 may be connected to one another via one or more
groups U, as defined above; and [0083] HetAr.sup.1 represents a
heteroaryl group having 5 to 20 aromatic ring atoms, which may be
substituted by one or more radicals R.sup.2.
[0084] HetAr.sup.1 is preferably selected from pyridine,
pyrimidine, pyridazine, pyrazine, triazine and benzimidazole, each
of which may be substituted by one or more radicals R.sup.2.
[0085] The above-mentioned groups R.sup.1-II are preferably
selected from phenyl, naphthyl, anthracenyl, phenanthrenyl,
benzanthracenyl, pyrenyl, biphenyl, terphenyl and quaterphenyl,
each of which may be substituted by one or more radicals
R.sup.2.
[0086] The above-mentioned groups R.sup.1-III preferably represent
groups of the following formula
##STR00009##
where the symbol * marks the bond to the remainder of the compound
and furthermore q and Ar.sup.2 are as defined above, where the
groups Ar.sup.2 may be connected to one another via one or more
groups U, as defined above.
[0087] Particularly preferred embodiments of compounds of the
formula (I) are the formulae depicted below:
##STR00010## ##STR00011##
where the symbols occurring are as defined above and furthermore
the compounds may be substituted by radicals R.sup.1 at all
unsubstituted positions.
[0088] Very particular preference is given to compounds of the
formulae (I-1), (I-2) and (I-3).
[0089] Particularly preferred embodiments of compounds of the
formula (II-A), (II-B) and (II-C) are the formulae depicted
below:
##STR00012## ##STR00013## ##STR00014## ##STR00015##
where the symbols occurring are as defined above and the group Z to
which the group L is bonded stands for a carbon atom, and where
furthermore the compounds may be substituted by radicals R.sup.1 at
all unsubstituted positions.
[0090] For the compounds of the formulae (II-A-1) to (II-A-7),
(II-B-1) to (II-B-7) and (II-C-1) to (II-C-5), the preferred
embodiments indicated above for the variable groups generally
apply.
[0091] In particular, it is preferred for these compounds for no or
1 or 2 groups Z per aromatic ring to be equal to N.
[0092] Furthermore, it is preferred for these compounds for Y to be
selected from C(R.sup.1).sub.2, NR.sup.0, O and S.
[0093] It is again furthermore preferred for these compounds for L
to be a single bond or to be selected from C.dbd.O, NR.sup.1, O, S,
alkylene groups having 1 to 10 C atoms or alkenylene groups having
2 to 10 C atoms, where one or more CH.sub.2 groups in the said
groups may be replaced by C.dbd.O, NR.sup.1, P(.dbd.O)(R.sup.1), O
or S, or arylene or heteroarylene groups having 5 to 20 aromatic
ring atoms, which may be substituted by one or more radicals
R.sup.1, or aromatic or heteroaromatic ring systems of the formula
(L-1).
[0094] Particular preference is given to compounds of the formulae
(II-A-1), (II-A-2), (II-A-3), (II-B-1), (II-B-2) and (II-B-3).
[0095] Still greater preference is given to compounds of the
following formulae
##STR00016## ##STR00017##
where R.sup.1 and L are as defined above.
[0096] For the compounds of the formulae (I-1-a) to (I-1-c),
(II-A-1-a) to (II-A-1-d), (II-B-1-a) and (II-C-1-a) to (II-C-1-d),
the preferred embodiments indicated above for the variable groups
generally apply.
[0097] It is especially preferred for the said compounds for them
to carry, as substituent R.sup.1, at least one group selected from
groups R.sup.1-I to R.sup.1-III defined above.
[0098] It is again furthermore preferred for these compounds for L
to be a single bond or to be selected from C.dbd.O, NR.sup.1, O, S,
alkylene groups having 1 to 10 C atoms or alkenylene groups having
2 to 10 C atoms, where one or more CH.sub.2 groups in the said
groups may be replaced by C.dbd.O, NR.sup.1, P(.dbd.O)(R.sup.1), O
or S, or arylene or heteroarylene groups having 5 to 20 aromatic
ring atoms, which may be substituted by one or more radicals
R.sup.1, or aromatic or heteroaromatic ring systems of the formula
(L-1).
[0099] Of the said compounds, particular preference is given to
compounds of the formulae (I-1-a), (I-1-b), (II-A-1-b), (II-B-1-a)
and (II-C-1-b).
[0100] Examples of compounds according to the invention are shown
in the following table:
TABLE-US-00001 ##STR00018## 1 ##STR00019## 2 ##STR00020## 3
##STR00021## 4 ##STR00022## 5 ##STR00023## 6 ##STR00024## 7
##STR00025## 8 ##STR00026## 9 ##STR00027## 10 ##STR00028## 11
##STR00029## 12 ##STR00030## 13 ##STR00031## 14 ##STR00032## 15
##STR00033## 16 ##STR00034## 17 ##STR00035## 18 ##STR00036## 19
##STR00037## 20 ##STR00038## 21 ##STR00039## 22 ##STR00040## 23
##STR00041## 24 ##STR00042## 25 ##STR00043## 26 ##STR00044## 27
##STR00045## 28 ##STR00046## 29 ##STR00047## 30 ##STR00048## 31
##STR00049## 32 ##STR00050## 33 ##STR00051## 34 ##STR00052## 35
##STR00053## 36 ##STR00054## 37 ##STR00055## 38 ##STR00056## 39
##STR00057## 40 ##STR00058## 41 ##STR00059## 42 ##STR00060## 43
[0101] The invention furthermore relates to a compound of the
formula (I) or (II) in which the group Q is selected equal to
CR.sup.1, where the following compounds are excluded:
##STR00061##
[0102] All embodiments of compounds which have been indicated as
preferred above in connection with contents of the electronic
device according to the invention are also preferred in relation to
the inventive subject-matter of the compounds themselves.
[0103] In particular, the index p, which indicates the number of
moieties bonded to L, is preferably equal to 2 or 3 and is
particularly preferably equal to 2.
[0104] According to a preferred embodiment, the sum of the values
for n in formula (I) is equal to 0 or 1, it is particularly
preferably equal to 0. According to a preferred embodiment, the sum
of the values for n per unit in square brackets with index p for
formula (II) is equal to 0 or 1, particularly preferably equal to
0.
[0105] For the group Z, this is generally preferably equal to
CR.sup.1. Furthermore preferably, not more than 2 adjacent groups Z
are equal to N. It is furthermore preferred for 0, 1, 2 or 3,
particularly preferably 0, 1 or 2, and very particularly preferably
0 or 1, Z per aromatic ring to be equal to N.
[0106] For the group Y, this is preferably selected on each
occurrence, identically or differently, from C(R.sup.1).sub.2,
NR.sup.0, O and S, particularly preferably from C(R.sup.1).sub.2
and NR.sup.0 and very particularly preferably from
C(R.sup.1).sub.2.
[0107] The compounds according to the invention can be prepared by
known organochemical synthetic methods. These include, for example,
Ullmann coupling, Hartwig-Buchwald coupling, Suzuki coupling and
brominations and cyclisations.
[0108] Scheme 1 below shows the synthesis of skeleton A, from which
compounds according to the invention can be prepared via subsequent
reactions.
##STR00062##
[0109] For the synthesis of skeleton A, firstly iodobenzene is
coupled to methyl 1H-indolo-2-carboxylate in an Ullmann reaction.
The resultant compound is then brominated by means of NBS. The
reaction of the resultant compound with methylmagnesium chloride
followed by a ring-closure reaction under dehydrating conditions
gives the corresponding bridged indolophenyl derivative.
[0110] Scheme 2 shows the synthesis of skeleton B. It differs from
the synthesis shown in Scheme 1 merely through the fact that,
instead of iodobenzene, 1,4-diiodobenzene is employed in the
Ullmann coupling with two equivalents of methyl
1H-indolo-2-carboxylate.
##STR00063##
[0111] Scheme 3a shows by way of example for skeleton A various
ways of obtaining compounds of the formula (I) according to the
invention by derivatisation reactions. An analogous procedure can
be used for skeleton B. In the first reaction shown, a Suzuki
reaction is carried out with a monoborono-functionalised aryl
derivative. In the second reaction shown, a corresponding
diarylamine is introduced as substituent on the indole by a
Buchwald reaction with a diarylamine.
##STR00064##
[0112] Scheme 3b shows by way of example how compounds of the
formula (II) according to the invention can be obtained from
intermediates of skeleton A. To this end, a
bis-diborono-functionalised aryl derivative, shown for the example
of 4,4'-diboronobiphenyl, is employed, so that a skeleton A is
coupled to each of the two borono-substituted positions of the aryl
derivative.
##STR00065##
[0113] Furthermore, other divalent aryl groups can also be employed
in the Suzuki coupling in such reactions, for example heteroaryl
groups, such as dibenzothiophene, or other aryl groups, such as
benzene, fluorene or terphenyl.
[0114] Scheme 4a shows by way of example for skeleton A further
ways of obtaining compounds of the formula (I) according to the
invention by derivatisation reactions. An analogous procedure can
be used for skeleton B. The intermediate obtained is a skeleton
C.
[0115] To this end, firstly a monobromination is carried out in
order to obtain the corresponding 5-bromoindole. An aryl group or a
diarylamine is subsequently introduced as substituent at position 5
of the indole ring by means of Suzuki reaction or Buchwald
reaction.
##STR00066##
[0116] Scheme 4b shows by way of example how compounds of the
formula (II) according to the invention can be obtained by an
analogous route to Scheme 4a through the use of bifunctional aryl
derivatives in the Buchwald coupling. To this end, a
bis-diborono-functionalised aryl derivative, shown for the example
of 1,3-diboronobenzene, is employed, to which two groups of
skeleton C are coupled.
##STR00067##
[0117] In reactions in accordance with Scheme 4b, compounds of
skeleton A can also be employed instead of compounds of skeleton C
in order to obtain alternative compounds of the formula (II).
Furthermore, other divalent aryl groups can also be employed in the
Buchwald coupling in such reactions, for example heteroaryl groups,
such as dibenzothiophene, or other aryl groups, such as benzene,
fluorene or terphenyl.
[0118] The synthetic routes described above are merely intended to
serve as examples. The person skilled in the art will be able to
fall back on alternative synthetic methods for the synthesis of the
compounds according to the invention if it appears advantageous to
him under the given circumstances. Furthermore, he will be able to
extend and/or modify the syntheses shown using his general expert
knowledge in the area of organic synthetic chemistry in order to
prepare compounds according to the invention.
[0119] The invention thus furthermore relates to a process for the
preparation of a compound of the formula (I) or (II) in which the
group Q is selected equal to CR.sup.1, characterised in that it
comprises at least one organometallic coupling reaction between an
indole derivative and a halogen-substituted aromatic or
heteroaromatic compound and at least one ring-closure reaction
between the indole derivative and the coupled aromatic or
heteroaromatic compound.
[0120] The compounds of the formula (I) or (II) described above, in
particular compounds which are substituted by reactive leaving
groups, such as bromine, iodine, chlorine, boronic acid or boronic
acid ester, can be used as monomers for the preparation of
oligomers, dendrimers or polymers. The oligomerisation or
polymerisation here preferably takes place via the halogen
functionality or the boronic acid functionality.
[0121] The invention therefore furthermore relates to oligomers,
polymers or dendrimers containing one or more compounds of the
formula (I) or (II), where the bond(s) to the polymer, oligomer or
dendrimer can be localised at any desired positions in formula (I)
or (II) which are substituted by R.sup.0 or R.sup.1. Depending on
the linking of the compound of the formula (I) or (II), the
compound is a constituent of a side chain of the oligomer or
polymer or a constituent of the main chain. An oligomer in the
sense of this invention is taken to mean a compound which is built
up from at least three monomer units. A polymer in the sense of the
invention is taken to mean a compound which is built up from at
least ten monomer units. The polymers, oligomers or dendrimers
according to the invention may be conjugated, partially conjugated
or non-conjugated. The oligomers or polymers according to the
invention may be linear, branched or dendritic. In the structures
linked in a linear manner, the units of the formula (I) or (II) may
be linked directly to one another or they may be linked to one
another via a divalent group, for example via a substituted or
unsubstituted alkylene group, via a heteroatom or via a divalent
aromatic or heteroaromatic group. In branched and dendritic
structures, for example, three or more units of the formula (I) or
(II) may be linked via a trivalent or polyvalent group, for example
via a trivalent or polyvalent aromatic or heteroaromatic group, to
form a branched or dendritic oligomer or polymer.
[0122] The same preferences as described above for compounds of the
formula (I) or (II) apply to the recurring units of the formula (I)
or (II) in oligomers, dendrimers and polymers.
[0123] For the preparation of the oligomers or polymers, the
monomers according to the invention are homopolymerised or
copolymerised with further monomers. Suitable and preferred
comonomers are selected from fluorenes (for example in accordance
with EP 842208 or WO 2000/22026), spirobifluorenes (for example in
accordance with EP 707020, EP 894107 or WO 2006/061181),
para-phenylenes (for example in accordance with WO 1992/18552),
carbazoles (for example in accordance with WO 2004/070772 or WO
2004/113468), thiophenes (for example in accordance with EP
1028136), dihydrophenanthrenes (for example in accordance with WO
2005/014689 or WO 2007/006383), cis- and trans-indenofluorenes (for
example in accordance with WO 2004/041901 or WO 2004/113412),
ketones (for example in accordance with WO 2005/040302),
phenanthrenes (for example in accordance with WO 2005/104264 or WO
2007/017066) or also a plurality of these units. The polymers,
oligomers and dendrimers usually also contain further units, for
example emitting (fluorescent or phosphorescent) units, such as,
for example, vinyltriarylamines (for example in accordance with WO
2007/068325) or phosphorescent metal complexes (for example in
accordance with WO 2006/003000), and/or charge-transport units, in
particular those based on triarylamines.
[0124] The polymers, oligomers and dendrimers according to the
invention have advantageous properties, in particular long
lifetimes, high efficiencies and good colour coordinates.
[0125] The polymers and oligomers according to the invention are
generally prepared by polymerisation of one or more types of
monomer, of which at least one monomer results in recurring units
of the formula (I) or (II) in the polymer. Suitable polymerisation
reactions are known to the person skilled in the art and are
described in the literature. Particularly suitable and preferred
polymerisation reactions which result in C--C or C--N links are the
following:
(A) SUZUKI polymerisation; (B) YAMAMOTO polymerisation; (C) STILLE
polymerisation; and (D) HARTWIG-BUCHWALD polymerisation.
[0126] The way in which the polymerisation can be carried out by
these methods and the way in which the polymers can then be
separated off from the reaction medium and purified is known to the
person skilled in the art and is described in detail in the
literature, for example in WO 2003/048225, WO 2004/037887 and WO
2004/037887.
[0127] The present invention thus also relates to a process for the
preparation of the polymers, oligomers and dendrimers according to
the invention, which is characterised in that they are prepared by
SUZUKI polymerisation, YAMAMOTO polymerisation, STILLE
polymerisation or HARTWIG-BUCHWALD polymerisation. The dendrimers
according to the invention can be prepared by processes known to
the person skilled in the art or analogously thereto. Suitable
processes are described in the literature, such as, for example, in
Frechet, Jean M. J.; Hawker, Craig J., "Hyperbranched polyphenylene
and hyperbranched polyesters: new soluble, three-dimensional,
reactive polymers", Reactive & Functional Polymers (1995),
26(1-3), 127-36; Janssen, H. M.; Meijer, E. W., "The synthesis and
characterization of dendritic molecules", Materials Science and
Technology (1999), 20 (Synthesis of Polymers), 403-458; Tomalia,
Donald A., "Dendrimer molecules", Scientific American (1995),
272(5), 62-6; WO 02/067343 A1 and WO 2005/026144 A1.
[0128] For the processing of the compounds formula (I) or (II) from
liquid phase, for example by spin coating or by printing processes,
formulations of the compounds are necessary. These formulations can
be, for example, solutions, dispersions or mini-emulsions.
[0129] The invention therefore furthermore relates to a
formulation, in particular a solution, dispersion or mini-emulsion,
comprising at least one compound of the formula (I) or (II) or at
least one polymer, oligomer or dendrimer containing at least one
unit of the formula (I) or (II) and at least one solvent,
preferably an organic solvent. The way in which solutions of this
type can be prepared is known to the person skilled in the art and
is described, for example, in the applications WO 2002/072714 and
WO 2003/019694 and the literature cited therein. Preference is
given to a formulation comprising at least one compound of the
formula (I) or (II), where the group Q is selected equal to
CR.sup.1, and at least one solvent.
[0130] The compounds of the formula (I) or (II) are suitable for
use in electronic devices, in particular in organic
electroluminescent devices (OLEDs). Depending on the substitution,
the compounds are preferably employed in certain functions and/or
layers.
[0131] For example, compounds of the formula (I) or (II) which
carry at least one group R.sup.1-I as substituent R.sup.1, as
defined above, are particularly suitable for use as matrix material
for phosphorescent dopants, as electron-transport material or as
hole-blocking material. The group R.sup.1-I here preferably
contains at least one electron-deficient group, such as
six-membered heteroaryl ring groups containing one or more nitrogen
atoms or five-membered heteroaryl ring groups containing two or
more nitrogen atoms.
[0132] Furthermore, compounds of the formula (I) or (II) which
carry at least one group R.sup.1-II and/or R.sup.1-III as
substituent R.sup.1, as defined above, are particularly suitable
for use as hole-transport materials or for use as fluorescent
dopants. The group R.sup.1-II here preferably contains an aromatic
ring system having 12 to 20 aromatic ring atoms.
[0133] The compounds of the formula (I) or (II) are preferably
employed as electron-transport material in an electron-transport
layer, as matrix material in an emitting layer or as hole-transport
material in a hole-transport layer. If the compounds are employed
as matrix materials in an emitting layer, the emitting layer
preferably comprises at least one phosphorescent emitter compound.
However, the compounds may also be employed in other layers and/or
functions, for example as fluorescent dopants in an emitting layer
or as hole- or electron-blocking materials.
[0134] The invention therefore furthermore relates to the use of
the compounds of the formula (I) or (II) in electronic devices. The
electronic devices here are preferably selected from the group
consisting of organic integrated circuits (O-ICs), organic
field-effect transistors (O-FETs), organic thin-film transistors
(O-TFTs), organic light-emitting transistors (O-LETs), organic
solar cells (O-SCs), organic optical detectors, organic
photoreceptors, organic field-quench devices (O-FQDs),
light-emitting electrochemical cells (LECs), organic laser diodes
(O-lasers) and particularly preferably selected from organic
electroluminescent devices (OLEDs).
[0135] The invention relates, as already mentioned above, to an
electronic device comprising anode, cathode and at least one
organic layer, where the organic layer comprises at least one
compound of the formula (I) or (II). The electronic device here is
preferably selected from the above-mentioned devices and is
particularly preferably an organic electroluminescent device.
[0136] Apart from cathode, anode and the emitting layer, the
organic electroluminescent device may also comprise further layers.
These are selected, for example, from in each case one or more
hole-injection layers, hole-trans-port layers, hole-blocking
layers, electron-transport layers, electron-injection layers,
electron-blocking layers, exciton-blocking layers,
charge-generation layers (IDMC 2003, Taiwan; Session 21 OLED (5),
T. Matsumoto, T. Nakada, J. Endo, K. Mori, N. Kawamura, A. Yokoi,
J. Kido, Multiphoton Organic EL Device Having Charge Generation
Layer), coupling-out layers and/or organic or inorganic p/n
junctions. However, it should be pointed out that each of these
layers does not necessarily have to be present and the choice of
layers is always dependent on the compounds used and in particular
also on whether the electroluminescent device is fluorescent or
phosphorescent. The compounds preferably employed in the respective
layers and functions are explicitly disclosed in later
sections.
[0137] It is preferred in accordance with the invention for the
compound of the formula (I) or (II) to be employed in an electronic
device comprising one or more phosphorescent dopants. The compound
can be used in various layers here, preferably in an
electron-transport layer, a hole-transport layer, a hole-injection
layer or in the emitting layer. However, the compound of the
formula (I) or (II) can also be employed in accordance with the
invention in an electronic device comprising one or more
fluorescent dopants and no phosphorescent dopants.
[0138] The term phosphorescent dopants typically encompasses
compounds in which the light emission takes place by a
spin-forbidden transition, for example a transition from an excited
triplet state or a state having a relatively high spin quantum
number, for example a quintet state.
[0139] Suitable phosphorescent dopants are, in particular,
compounds which emit light, preferably in the visible region, on
suitable excitation and in addition contain at least one atom
having an atomic number greater than 20, preferably greater than 38
and less than 84, particularly preferably greater than 56 and less
than 80. The phosphorescent dopants used are preferably compounds
which contain copper, molybdenum, tungsten, rhenium, ruthenium,
osmium, rhodium, iridium, palladium, platinum, silver, gold or
europium, in particular compounds which contain iridium, platinum
or copper.
[0140] For the purposes of the present invention, all luminescent
iridium, platinum or copper complexes are regarded as
phosphorescent compounds.
[0141] Examples of the phosphorescent dopants described above are
revealed by the applications WO 2000/70655, WO 2001/41512, WO
2002/02714, WO 2002/15645, EP 1191613, EP 1191612, EP 1191614, WO
2005/033244, WO 2005/019373 and US 2005/0258742. In general, all
phosphorescent complexes as used in accordance with the prior art
for phosphorescent OLEDs and as are known to the person skilled in
the art in the area of organic electroluminescent devices are
suitable. The person skilled in the art will also be able to employ
further phosphorescent complexes without inventive step in
combination with the compounds according to the invention in
organic electroluminescent devices. Further examples of suitable
phosphorescent dopants are revealed by the table following in a
later section.
[0142] In a preferred embodiment of the present invention, the
compounds of the formula (I) or (II) are employed as matrix
material in combination with one or more dopants, preferably
phosphorescent dopants. The compounds are particularly suitable for
use as matrix material if they contain one or more groups of the
formula R.sup.1-I, such as, for example, six-membered heteroaryl
ring groups containing one or more nitrogen atoms or five-membered
heteroaryl ring groups containing two or more nitrogen atoms.
[0143] A dopant in a system comprising a matrix material and a
dopant is taken to mean the component whose proportion in the
mixture is the smaller. Correspondingly, a matrix material is taken
to mean the component whose proportion in the mixture is the
greater in a system comprising a matrix material and a dopant.
[0144] The proportion of the matrix material in the emitting layer
is in this case between 50.0 and 99.9% by vol., preferably between
80.0 and 99.5% by vol. and particularly preferably between 92.0 and
99.5% by vol. for fluorescent emitting layers and between 85.0 and
97.0% by vol. for phosphorescent emitting layers.
[0145] Correspondingly, the proportion of the dopant is between 0.1
and 50.0% by vol., preferably between 0.5 and 20.0% by vol. and
particularly preferably between 0.5 and 8.0% by vol. for
fluorescent emitting layers and between 3.0 and 15.0% by vol. for
phosphorescent emitting layers.
[0146] An emitting layer of an organic electroluminescent device
may also comprise systems comprising a plurality of matrix
materials (mixed-matrix systems) and/or a plurality of dopants. In
this case too, the dopants are generally the materials whose
proportion in the system is the smaller and the matrix materials
are the materials whose proportion in the system is the greater. In
individual cases, however, the proportion of an individual matrix
material in the system may be smaller than the proportion of an
individual dopant.
[0147] In a further preferred embodiment of the invention, the
compounds of the formula (I) or (II) are used as a component of
mixed-matrix systems. The mixed-matrix systems preferably comprise
two or three different matrix materials, particularly preferably
two different matrix materials. One of the two materials here is
preferably a material having hole-transporting properties and the
other material is a material having electron-transporting
properties. The two different matrix materials here may be present
in a ratio of 1:50 to 1:1, preferably 1:20 to 1:1, particularly
preferably 1:10 to 1:1 and very particularly preferably 1:4 to 1:1.
Mixed-matrix systems are preferably employed in phosphorescent
organic electroluminescent devices.
[0148] The mixed-matrix systems may comprise one or more dopants.
The dopant compound or the dopant compounds together have, in
accordance with the invention, a proportion of 0.1 to 50.0% by vol.
in the mixture as a whole and preferably a proportion of 0.5 to
20.0% by vol. in the mixture as a whole. Correspondingly, the
matrix components together have a proportion of 50.0 to 99.9% by
vol. in the mixture as a whole and preferably a proportion of 80.0
to 99.5% by vol. in the mixture as a whole.
[0149] Particularly suitable matrix materials, which can be
employed in combination with the compounds according to the
invention as matrix components of a mixed-matrix system, are
aromatic ketones, aromatic phosphine oxides or aromatic sulfoxides
or sulfones, for example in accordance with WO 2004/013080, WO
2004/093207, WO 2006/005627 or WO 2010/006680, triarylamines,
carbazole derivatives, for example CBP (N,N-biscarbazolylbiphenyl)
or the carbazole derivatives disclosed in WO 2005/039246, US
2005/0069729, JP 2004/288381, EP 1205527 or WO 2008/086851,
indolocarbazole derivatives, for example in accordance with WO
2007/063754 or WO 2008/056746, azacarbazole derivatives, for
example in accordance with EP 1617710, EP 1617711, EP 1731584, JP
2005/347160, bipolar matrix materials, for example in accordance
with WO 2007/137725, silanes, for example in accordance with WO
2005/111172, azaboroles or boronic esters, for example in
accordance with WO 2006/117052, triazine derivatives, for example
in accordance with WO 2010/015306, WO 2007/063754 or WO
2008/056746, zinc complexes, for example in accordance with EP
652273 or WO 2009/062578, diazasilole or tetraazasilole
derivatives, for example in accordance with WO 2010/054729,
diazaphosphole derivatives, for example in accordance with WO
2010/054730, or indenocarbazole derivatives, for example in
accordance with WO 10/136,109 and WO 2011/000455, or bridged
carbazoles, for example in accordance with WO 2011/088877 and WO
2011/128017.
[0150] Preferred phosphorescent dopants for use in mixed-matrix
systems comprising the compounds according to the invention are the
phosphorescent dopants shown in a following table.
[0151] In a further preferred embodiment of the invention, the
compounds of the formula (I) or (II) are employed as hole-transport
material. The compounds are then preferably employed in a
hole-transport layer and/or in a hole-injection layer. A
hole-injection layer in the sense of this invention is a layer
which is directly adjacent to the anode. A hole-transport layer in
the sense of this invention is a layer which is located between the
hole-injection layer and the emission layer. The compounds are used
as hole-transport material if, in particular, they are substituted
by one or more aromatic ring systems having 12 to 20 aromatic ring
atoms and/or by one or more arylamino groups.
[0152] If the compound of the formula (I) or (II) is employed as
hole-transport material in a hole-transport layer, the compound can
be employed as pure material, i.e. in a proportion of 100%, in the
hole-transport layer or it can be employed in combination with
further compounds in the hole-transport layer.
[0153] In a further embodiment of the invention, the compounds of
the formula (I) or (II) are employed as fluorescent dopants in an
emitting layer. In particular, the compounds are suitable as
fluorescent dopants if they are substituted by one or more aromatic
systems, preferably aromatic systems containing 12 to 20 aromatic
ring atoms. The compounds according to the invention are preferably
used as green or blue emitters.
[0154] The proportion of the compound of the formula (I) or (II) as
dopant in the mixture of the emitting layer is in this case between
0.1 and 50.0% by vol., preferably between 0.5 and 20.0% by vol.,
particularly preferably between 0.5 and 8.0% by vol.
Correspondingly, the proportion of the matrix material is between
50.0 and 99.9% by vol., preferably between 80.0 and 99.5% by vol.,
particularly preferably between 92.0 and 99.5% by vol.
[0155] Preferred matrix materials for use in combination with the
compounds according to the invention as fluorescent dopants are
mentioned in one of the following sections. They correspond to the
matrix materials for fluorescent dopants that are indicated as
preferred.
[0156] In a further embodiment of the invention, the compounds are
employed as electron-transport materials in an electron-transport
layer of an organic electroluminescent device. The compounds are
particularly suitable for use as electron-transport material if
they contain one or more groups of the formula R.sup.1-I, such as,
for example, six-membered heteroaryl ring groups containing one or
more, nitrogen atoms or five-membered heteroaryl ring groups
containing two or more nitrogen atoms.
[0157] The organic electroluminescent device may also comprise a
plurality of emitting layers. These emission layers in this case
particularly preferably have in total a plurality of emission
maxima between 380 nm and 750 nm, resulting overall in white
emission, i.e. various emitting compounds which are able to
fluoresce or phosphoresce and which emit blue or yellow or orange
or red light are used in the emitting layers, where the various
colours in this embodiment of the invention together give white
light. Particular preference is given to three-layer systems, i.e.
systems having three emitting layers, where one or more of these
layers comprises a compound of the formula (I) or (II) and where
the three layers exhibit blue, green and orange or red emission
(for the basic structure see, for example, WO 2005/011013).
Likewise, emitters which have broad-band emission bands and thus
exhibit white emission are suitable for white emission in such
systems. Alternatively and/or additionally, the compounds according
to the invention may also be present in a hole-transport layer or
electron-transport layer or in another layer in such systems.
[0158] The further functional materials preferably employed in the
electronic devices comprising one or more compounds of the formula
(I) or (II) are shown below.
[0159] The compounds shown in the following table are particularly
suitable phosphorescent dopants.
TABLE-US-00002 ##STR00068## ##STR00069## ##STR00070## ##STR00071##
##STR00072## ##STR00073## ##STR00074## ##STR00075## ##STR00076##
##STR00077## ##STR00078## ##STR00079## ##STR00080## ##STR00081##
##STR00082## ##STR00083## ##STR00084## ##STR00085## ##STR00086##
##STR00087## ##STR00088## ##STR00089## ##STR00090## ##STR00091##
##STR00092## ##STR00093## ##STR00094## ##STR00095## ##STR00096##
##STR00097## ##STR00098## ##STR00099## ##STR00100## ##STR00101##
##STR00102## ##STR00103## ##STR00104## ##STR00105## ##STR00106##
##STR00107## ##STR00108## ##STR00109## ##STR00110## ##STR00111##
##STR00112## ##STR00113## ##STR00114## ##STR00115## ##STR00116##
##STR00117## ##STR00118## ##STR00119## ##STR00120## ##STR00121##
##STR00122## ##STR00123## ##STR00124## ##STR00125## ##STR00126##
##STR00127## ##STR00128## ##STR00129## ##STR00130## ##STR00131##
##STR00132## ##STR00133## ##STR00134## ##STR00135## ##STR00136##
##STR00137## ##STR00138## ##STR00139## ##STR00140## ##STR00141##
##STR00142## ##STR00143## ##STR00144## ##STR00145## ##STR00146##
##STR00147## ##STR00148## ##STR00149## ##STR00150## ##STR00151##
##STR00152## ##STR00153## ##STR00154## ##STR00155## ##STR00156##
##STR00157## ##STR00158## ##STR00159## ##STR00160## ##STR00161##
##STR00162## ##STR00163## ##STR00164## ##STR00165## ##STR00166##
##STR00167## ##STR00168## ##STR00169## ##STR00170## ##STR00171##
##STR00172## ##STR00173## ##STR00174## ##STR00175## ##STR00176##
##STR00177## ##STR00178## ##STR00179## ##STR00180## ##STR00181##
##STR00182## ##STR00183## ##STR00184## ##STR00185## ##STR00186##
##STR00187## ##STR00188## ##STR00189## ##STR00190## ##STR00191##
##STR00192##
##STR00193## ##STR00194## ##STR00195## ##STR00196## ##STR00197##
##STR00198## ##STR00199## ##STR00200## ##STR00201## ##STR00202##
##STR00203## ##STR00204## ##STR00205## ##STR00206## ##STR00207##
##STR00208##
[0160] Preferred fluorescent dopants are selected from the class of
the monostyrylamines, the distyrylamines, the tristyrylamines, the
tetrastyrylamines, the styrylphosphines, the styryl ethers and the
arylamines. A monostyrylamine is taken to mean a compound which
contains one substituted or unsubstituted styryl group and at least
one, preferably aromatic, amine. A distyrylamine is taken to mean a
compound which contains two substituted or unsubstituted styryl
groups and at least one, preferably aromatic, amine. A
tristyrylamine is taken to mean a compound which contains three
substituted or unsubstituted styryl groups and at least one,
preferably aromatic, amine. A tetrastyrylamine is taken to mean a
compound which contains four substituted or unsubstituted styryl
groups and at least one, preferably aromatic, amine. The styryl
groups are particularly preferably stilbenes, which may also be
further substituted. Corresponding styrylphosphines and styryl
ethers are defined analogously to the amines. An arylamine or
aromatic amine in the sense of this invention is taken to mean a
compound which contains three substituted or unsubstituted aromatic
or heteroaromatic ring systems bonded directly to the nitrogen. At
least one of these aromatic or heteroaromatic ring systems is
preferably a condensed ring system, particularly preferably having
at least 14 aromatic ring atoms. Preferred examples thereof are
aromatic anthracenamines, aromatic anthracenediamines, aromatic
pyrenamines, aromatic pyrenediamines, aromatic chrysenamines or
aromatic chrysenediamines. An aromatic anthracenamine is taken to
mean a compound in which one diarylamino group is bonded directly
to an anthracene group, preferably in the 9-position. An aromatic
anthracenediamine is taken to mean a compound in which two
diarylamino groups are bonded directly to an anthracene group,
preferably in the 9,10-position. Aromatic pyrenamines,
pyrenediamines, chrysenamines and chrysenediamines are defined
analogously thereto, where the diarylamino groups are preferably
bonded to the pyrene in the 1-position or in the 1,6-position.
Further preferred fluorescent dopants are selected from
indenofluorenamines or indenofluorenediamines, for example in
accordance with WO 2006/122630, benzoindenofluorenamines or
benzoindenofluorenediamines, for example in accordance with WO
2008/006449, and dibenzoindenofluorenamines or
dibenzoindenofluorenediamines, for example in accordance with WO
2007/140847. Examples of fluorescent dopants from the class of the
styrylamines are substituted or unsubstituted tristilbenamines or
the fluorescent dopants described in WO 2006/000388, WO
2006/058737, WO 2006/000389, WO 2007/065549 and WO 2007/115610.
Preference is furthermore given to the condensed hydrocarbons
disclosed in WO 2010/012328. Furthermore, the compounds of the
formula (I) or (II) can also be used as fluorescent dopants.
[0161] Suitable fluorescent dopants are furthermore the structures
disclosed in JP 2006/001973, WO 2004/047499, WO 2006/098080, WO
2007/065678, US 2005/0260442 and WO 2004/092111.
[0162] Suitable matrix materials, preferably for fluorescent
dopants, are materials from various classes of substance. Preferred
matrix materials are selected from the classes of the oligoarylenes
(for example 2,2',7,7'-tetraphenylspirobifluorene in accordance
with EP 676461 or dinaphthylanthracene), in particular the
oligoarylenes containing condensed aromatic groups, the
oligoarylenevinylenes (for example DPVBi or spiro-DPVBi in
accordance with EP 676461), the polypodal metal complexes (for
example in accordance with WO 2004/081017), the hole-conducting
compounds (for example in accordance with WO 2004/058911), the
electron-conducting compounds, in particular ketones, phosphine
oxides, sulfoxides, etc. (for example in accordance with WO
2005/084081 and WO 2005/084082), the atropisomers (for example in
accordance with WO 2006/048268), the boronic acid derivatives (for
example in accordance with WO 2006/117052) or the benzanthracenes
(for example in accordance with WO 2008/145239). Preferred matrix
materials are furthermore the compounds of the formula (I) or (II).
Particularly preferred matrix materials are selected from the
classes of the oligoarylenes, comprising naphthalene, anthracene,
benzanthracene and/or pyrene or atropisomers of these compounds,
the oligoarylenevinylenes, the ketones, the phosphine oxides and
the sulfoxides. Very particularly preferred matrix materials are
selected from the classes of the oligoarylenes, comprising
anthracene, benzanthracene, benzophenanthrene and/or pyrene or
atropisomers of these compounds. An oligoarylene in the sense of
this invention is intended to be taken to mean a compound in which
at least three aryl or arylene groups are bonded to one
another.
[0163] Suitable matrix materials, preferably for fluorescent
dopants, are disclosed, for example, in WO 2004/018587, WO
2008/006449, U.S. Pat. No. 5,935,721, US 2005/0181232, JP
2000/273056, EP 681019, US 2004/0247937 and US 2005/0211958.
[0164] Preferred matrix materials for phosphorescent dopants are
carbazole derivatives (for example CBP, N,N-biscarbazolylbiphenyl)
or compounds in accordance with WO 2005/039246, US 2005/0069729, JP
2004/288381, EP 1205527 or WO 2008/086851), triarylamines,
azacarbazoles (for example in accordance with EP 1617710, EP
1617711, EP 1731584, JP 2005/347160), indolocarbazole derivatives
(for example in accordance with WO 2007/063754 or WO 2008/056746),
ketones (for example in accordance with WO 2004/093207 or WO
2010/006680), phosphine oxides, sulfoxides and sulfones (for
example in accordance with WO 2005/003253), oligophenylenes,
aromatic amines (for example in accordance with US 2005/0069729),
bipolar matrix materials (for example in accordance with WO
2007/137725), silanes (for example in accordance with WO
2005/111172), azaboroles or boronic esters (for example in
accordance with WO 2006/117052), triazine derivatives (for example
in accordance with WO 2010/015306, WO 2007/063754 or WO
2008/056746), zinc complexes (for example in accordance with WO
2009/062578), aluminium complexes (for example BAlq), diazasilole
and tetraazasilole derivatives, for example in accordance with WO
2010/054730, indenocarbazole derivatives, for example in accordance
with WO 2010/136109 and WO 2011/000455 or diazaphospholes, for
example in accordance with WO 2010/054730.
[0165] Suitable charge-transport materials, as can be used in the
hole-injection or hole-transport layer or in the electron-transport
layer of the organic electroluminescent device according to the
invention, are, for example, the compounds disclosed in Y. Shirota
et al., Chem. Rev. 2007, 107(4), 953-1010, or other materials as
are employed in these layers in accordance with the prior art.
[0166] The cathode preferably comprises metals having a low work
function, metal alloys or multilayered structures comprising
various metals, such as, for example, alkaline-earth metals, alkali
metals, main-group metals or lanthanoids (for example Ca, Ba, Mg,
Al, In, Mg, Yb, Sm, etc.). Also suitable are alloys comprising an
alkali metal or alkaline-earth metal and silver, for example an
alloy comprising magnesium and silver. In the case of multilayered
structures, further metals which have a relatively high work
function, such as, for example, Ag or Al, can also be used in
addition to the said metals, in which case combinations of the
metals, such as, for example, Ca/Ag, Ba/Ag, Ba/Al or Mg/Ag, are
generally used. It may also be preferred to introduce a thin
interlayer of a material having a high dielectric constant between
a metallic cathode and the organic semiconductor. Suitable for this
purpose are, for example, alkali metal fluorides or alkaline-earth
metal fluorides, but also the corresponding oxides or carbonates
(for example LiF, Li.sub.2O, BaF.sub.2, MgO, NaF, CsF,
Cs.sub.2CO.sub.3, etc.). Furthermore, lithium quinolinate (LiQ) can
be used for this purpose. The layer thickness of this layer is
preferably between 0.5 and 5 nm.
[0167] The anode preferably comprises materials having a high work
function. The anode preferably has a work function of greater than
4.5 eV vs. vacuum. Suitable for this purpose are on the one hand
metals having a high redox potential, such as, for example, Ag, Pt
or Au. On the other hand, metal/metal oxide electrodes (for example
Al/Ni/NiO.sub.x, Al/PtO.sub.x) may also be preferred. For some
applications, at least one of the electrodes must be transparent or
partially transparent in order to facilitate either irradiation of
the organic material (organic solar cells) or the coupling-out of
light (OLEDs, O-lasers). Preferred anode materials here are
conductive mixed metal oxides. Particular preference is given to
indium tin oxide (ITO) or indium zinc oxide (IZO). Preference is
furthermore given to conductive, doped organic materials, in
particular conductive, doped polymers.
[0168] The device is appropriately (depending on the application)
structured, provided with contacts and finally sealed, since the
lifetime of the devices according to the invention is shortened in
the presence of water and/or air.
[0169] In a preferred embodiment, the organic electroluminescent
device according to the invention is characterised in that one or
more layers are coated by means of a sublimation process, in which
the materials are applied by vapour deposition in vacuum
sublimation units at an initial pressure of less than 10.sup.-6
mbar, preferably less than 10.sup.-6 mbar. However, it is also
possible here for the initial pressure to be even lower, for
example less than 10.sup.-7 mbar.
[0170] Preference is likewise given to an organic
electroluminescent device, characterised in that one or more layers
are coated by means of the OVPD (organic vapour phase deposition)
process or with the aid of carrier-gas sublimation, in which the
materials are applied at a pressure of between 10.sup.-5 mbar and 1
bar. A special case of this process is the OVJP (organic vapour jet
printing) process, in which the materials are applied directly
through a nozzle and are thus structured (for example M. S. Arnold
et al., Appl. Phys. Lett. 2008, 92, 053301).
[0171] Preference is furthermore given to an organic
electroluminescent device, characterised in that one or more layers
are produced from solution, such as, for example, by spin coating,
or by means of any desired printing process, such as, for example,
screen printing, flexographic printing, nozzle printing or offset
printing, but particularly preferably LITI (light induced thermal
imaging, thermal transfer printing) or ink-jet printing. Soluble
compounds of the formula (I) or (II) are necessary for this
purpose. High solubility can be achieved through suitable
substitution of the compounds.
[0172] For the production of an organic electroluminescent device
according to the invention, it is furthermore preferred to apply
one or more layers from solution and one or more layers by a
sublimation process.
[0173] The organic electroluminescent devices comprising one or
more compounds according to the invention can be employed in
displays, as light sources in lighting applications and as light
sources in medical and/or cosmetic applications (for example light
therapy).
[0174] On use of the compounds of the formula (I) or (II) in an
organic electroluminescent device, one or more of the advantages
mentioned below can be achieved:
[0175] The compounds according to the invention are very highly
suitable for use as matrix materials for phosphorescent dopants and
for use as electrontransport materials. On use of the compounds
according to the invention in these functions, good power
efficiencies, low operating voltages and good lifetimes of the
organic electroluminescent devices are obtained.
[0176] Furthermore, the compounds according to the invention are
distinguished by high oxidation stability in solution, which has an
advantageous effect during purification and handling of the
compounds and on use thereof in electronic devices.
[0177] Furthermore, the compounds according to the invention are
temperature-stable and can thus be sublimed substantially without
decomposition. Purification of the compounds is thus simplified,
and the compounds can be obtained in higher purity, which has a
positive effect on the performance data of the electronic devices
comprising the materials. In particular, devices having longer
operating lifetimes can thus be produced.
[0178] The invention is explained in greater detail by the
following working examples, with the invention not being restricted
to the scope of the examples.
USE EXAMPLES
A) Synthesis Examples
[0179] The following syntheses are carried out, unless indicated
otherwise, under a protective-gas atmosphere in dried solvents. The
solvents and reagents indicated are commercially available.
Example 1
11-[3-(4,6-Diphenyl-1,3,5-triazin-2-yl)phenyl]-10,10-dimethyl-10H-indolo[1-
,2-a]indole
##STR00209##
[0180] 1st Step:
[0181] 50 g (285 mmol) of 2-methyl indole-2-carboxylate, 116.4 g
(571 mmol) of iodobenzene and 98.5 g of K.sub.2CO.sub.3 (712.5
mmol) are suspended in 11 of toluene. 15.8 g (114 mmol) of CuI and
10.06 g of N,N'-dimethylenediamine (114 mmol) are added to this
suspension. The reaction mixture is heated under reflux for 48 h.
After cooling, the precipitate is filtered off via a fluted filter.
The reaction solution is subsequently partitioned between ethyl
acetate and water, the organic phase is washed three times with
water, dried over Na.sub.2SO.sub.4 and evaporated in vacuo. The
black-green oil remaining is filtered through silica gel with
heptane:toluene. The evaporated filtrate residue is subsequently
recrystallised from methanol. Yield: 57 g of
1-phenyl-1H-indole-2-methylcarboxylate (80%)
2nd Step:
[0182] 57 g (227 mmol) of 1-phenyl-1H-indole-2-methylcarboxylate
are initially introduced in 500 ml of dimethylformamide. A solution
of 40.4 g (227 mmol) of NBS in 100 ml of dimethylformamide is
subsequently added dropwise at 0.degree. C. with exclusion of
light, the mixture is allowed to come to RT and is stirred at this
temperature for a further 4 h. The mixture is subsequently poured
into ice-water. The precipitate is filtered, washed with water and
subsequently washed with heptane. The product is washed by stirring
with hot heptane and filtered off with suction. Yield: 71.1 g,
(95%)
3rd Step:
[0183] 57.48 g of anhydrous cerium(III) chloride (233 mmol) is
initially introduced in 700 ml of dry THF. 70 g (212 mmol) of
1-phenyl-3-bromo-1H-indole-2-methylcarboxylate are metered into
this solution in portions, and the mixture is stirred for 1 h. The
reaction mixture is cooled, and 212 ml (636 mmol) of
methylmagnesium chloride solution (3 mol/l in THF) are added
dropwise at 5.degree. C. over the course of 40 min. After one hour,
the reaction mixture is carefully poured onto ice and extracted
three times with dichloromethane. The combined organic phases are
dried over Na.sub.2SO.sub.4 and evaporated. The residue is
recrystallised from toluene. Yield: 65.8 g (94%)
4th Step:
[0184] 157 g of polyphosphoric acid (1.6 mol) and 104 g of
methanesulfonic acid (1.1 mol) are initially introduced in 11 of
CH.sub.2Cl.sub.2. 65 g (197 mmol) of
2-(3-bromo-1-phenyl-1H-indol-2-yl)propan-2-ol in dichloromethane
solution (150 ml) are added dropwise to this solution over the
course of 30 min, and the mixture is stirred at 50.degree. C. for 1
h. After this time, the reaction mixture is cooled, carefully
poured onto ice and extracted three times with dichloromethane. The
combined organic phases are dried over Na.sub.2SO.sub.4 and
evaporated. The residue is recrystallised from toluene. Yield: 52.3
g of 11-bromo-10,10-dimethyl-10H-indolo[1,2-a]indole (85%)
5th Step:
[0185] 20 g (57 mmol) of
11-bromo-10,10-dimethyl-10H-indolo[1,2-a]indole, 25 g (57 mmol) of
2,4-diphenyl-6-[3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,-
3,5-triazine and 86 ml of a 2M sodium carbonate solution are
suspended in 500 ml of ethylene glycol dimethyl ether. 1.66 g (1.43
mmol) of Pd(PPh.sub.3).sub.4 are added to this suspension. The
reaction mixture is heated under reflux for 5 h. After cooling, the
precipitated solid is filtered off with suction and washed with
water and ethanol and dried. The residue is extracted with hot
toluene, recrystallised from toluene and finally sublimed in a high
vacuum. The purity is 99.9%. Yield: 19.5 g (59%).
Example 2
Bisbiphenyl-4-yl-[4-(11,11-dimethyl-1H-indolo[1,2-a]indol-10-yl)phenyl]ami-
ne
##STR00210##
[0187] 20 g (64 mmol) of
11-bromo-10,10-dimethyl-10H-indolo[1,2-a]indole (4th step of
Example 1), 33.5 g (64 mmol) of
bisbiphenyl-4-yl-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]a-
mine and 96 ml of a 2M sodium carbonate solution are suspended in
500 ml of ethylene glycol dimethyl ether. 1.66 g (1.43 mmol) of
Pd(PPh.sub.3).sub.4 are added to this suspension. The reaction
mixture is heated under reflux for 10 h. After cooling, the
precipitated solid is filtered off with suction, washed with water
and ethanol and dried. The residue is extracted with hot toluene,
recrystallised from toluene and subsequently sublimed in a high
vacuum. The purity is 99.9%. Yield: 26 g (65%).
Example 3
Bis-10,10'-[(4-4'-biphenyl)-11,11-dimethyl-1H-indolo-[1,2-a]indole
##STR00211##
[0189] 30 g (96 mmol) of
11-bromo-10,10-dimethyl-10H-indolo[1,2-a]indole (4th step of
Example 1), 11.6 g (48 mmol) of 4,4'-biphenyldiboronic acid and 145
ml of a 2M sodium carbonate solution are suspended in 600 ml of
ethylene glycol dimethyl ether. 2.77 g (2.4 mmol) of
Pd(PPh.sub.3).sub.4 are added to this suspension. The reaction
mixture is heated under reflux for 12 h. After cooling, the
precipitated solid is filtered off with suction, washed with water
and ethanol and dried. The residue is extracted with hot toluene,
recrystallised from toluene and subsequently sublimed in a high
vacuum. The purity is 99.9%. Yield: 35.6 g (60%).
Example 4
##STR00212##
[0190] 1st Step:
[0191] 50 g (285 mmol) of 2-methyl indole-2-carboxylate, 47 g (143
mmol) of 1,4-diiodobenzene and 98.5 g of K.sub.2CO.sub.3 (712.5
mmol) are suspended in 11 of toluene. 15.8 g (114 mmol) of CuI and
10.06 g of N,N'-dimethylenediamine (114 mmol) are added to this
suspension. The reaction mixture is heated under reflux for 48 h.
After cooling, the precipitate is filtered off via a fluted filter.
The reaction solution is subsequently partitioned between ethyl
acetate and water, the organic phase is washed three times with
water, dried over Na.sub.2SO.sub.4 and evaporated in a rotary
evaporator. The black-green oil remaining is filtered through
silica gel with heptane:toluene. The evaporated filtrate residue is
recrystallised from methanol. Yield: 48.5 g of
1,4-di(1H-indole-2-methylcarboxylat-1-yl)benzene (80%).
2nd Step:
[0192] 45 g (106 mmol) of
1,4-di-(1H-indole-2-methylcarboxylat-1-yl)benzene is initially
introduced in 500 ml of dimethylformamide. A solution of 37.5 g
(212 mmol) of NBS in 100 ml of dimethylformamide is subsequently
added dropwise at 0.degree. C. with exclusion of light, the mixture
is allowed to come to RT and is stirred at this temperature for a
further 4 h. The mixture is subsequently poured into ice-water. The
precipitate is filtered, washed with water and subsequently washed
with heptane. The product is washed by stirring with hot heptane
and filtered off with suction. Yield: 55.5 g (90%).
3rd Step:
[0193] 30.9 g of anhydrous cerium(III) chloride (172 mmol) is
initially introduced in 700 ml of dry THF. 50 g (85.9 mmol) of
1,4-di(1H-indole-3-bromo-2-methylcarboxylat-1-yl)benzene are
metered into this solution in portions, and the mixture is stirred
for 1 h. The reaction mixture is cooled, and 200 ml (601 mmol) of
methylmagnesium chloride solution (3 mol/l in THF) are added
dropwise over the course of 40 min at 5.degree. C. After one hour,
the reaction mixture is carefully poured onto ice and extracted
three times with dichloromethane. The combined organic phases are
dried over Na.sub.2SO.sub.4 and evaporated. The residue is
recrystallised from toluene. Yield: 47 g (95%).
4th Step:
[0194] 26 g of polyphosphoric acid (270 mmol) and 25.9 g of
methanesulfonic acid (270 mmol) are initially introduced in 500 ml
of CH.sub.2Cl.sub.2. 45 g (77.3 mmol) of the compound from step 3
in dichloromethane solution (150 ml) are added dropwise to this
solution over the course of 30 min, and the mixture is stirred at
50.degree. C. for 1 h. After this time, the reaction mixture is
cooled, carefully poured onto ice and extracted three times with
dichloromethane. The combined organic phases are dried over
Na.sub.2SO.sub.4 and evaporated. The residue is recrystallised from
toluene. Yield: 39.2 g (90%).
5th Step:
[0195] 35 g (62 mmol) of the compound from the 4th step, 15 g (124
mmol) of phenylboronic acid and 124 ml of a 2M sodium carbonate
solution are suspended in 700 ml of ethylene glycol dimethyl ether.
3.58 g (3.1 mmol) of Pd(PPh.sub.3).sub.4 are added to this
suspension. The reaction mixture is heated under reflux for 5 h.
After cooling, the precipitated solid is filtered off with suction,
washed with water and ethanol and dried. The residue is extracted
with hot toluene, recrystallised from toluene and subsequently
sublimed in a high vacuum. The purity is 99.9%. Yield: 21.8 g
(65%).
B) Device Examples
[0196] OLEDs according to the invention are produced by a general
process in accordance with WO 2004/058911, which is adapted to the
circumstances described here (layer-thickness variation,
materials).
[0197] The data for various OLEDs are presented in Examples E1 to
E9 below (see Tables 1 and 2). Glass plates coated with structured
ITO (indium tin oxide) in a thickness of 150 nm are coated with 20
nm of PEDOT (poly(3,4-ethylenedioxy-2,5-thiophene), applied by spin
coating from water; purchased from H. C. Starck, Goslar, Germany)
for improved processing. These coated glass plates form the
substrates to which the OLEDs are applied. The OLEDs basically have
the following layer structure: substrate/optional hole-injection
layer (HIL)/hole-transport layer (HTL)/optional interlayer
(IL)/electron-blocking layer (EBL)/emission layer (EML)/optional
hole-blocking layer (HBL)/electron-transport layer (ETL)/optional
electron-injection layer (EIL) and finally a cathode. The cathode
is formed by an aluminium layer with a thickness of 100 nm. The
precise structure of the OLEDs is shown in Table 1. The materials
required for the production of the OLEDs are shown in Table 3.
[0198] All materials are applied by thermal vapour deposition in a
vacuum chamber. The emission layer here always consists of at least
one matrix material (host material) and an emitting dopant
(emitter), to which the matrix material or materials is (are)
admixed by co-evaporation in a certain proportion by volume. An
expression such as IC1:3:TEG1 (70%:20%:10%) here means that
material IC1 is present in the layer in a proportion by volume of
70%, 3 is present in the layer in a proportion of 20% and TEG1 is
present in the layer in a proportion of 10%. Analogously, the
electrontransport layer may also consist of a mixture of two
materials.
[0199] The OLEDs are characterised by standard methods. For this
purpose, the electroluminescence spectra, the current efficiency
(measured in cd/A), the power efficiency (measured in Im/W) and the
external quantum efficiency (EQE, measured in percent) as a
function of the luminous density, calculated from
current/voltage/luminous density characteristic lines (IUL
characteristic lines) assuming Lambert emission characteristics)
are determined. The electroluminescence spectra are determined at a
luminous density of 1000 cd/m.sup.2, and the CIE 1931.times. and y
colour coordinates are calculated therefrom. The expression U1000
in Table 2 denotes the voltage required for a luminous density of
1000 cd/m.sup.2. CE1000 and PE1000 denote the current and power
efficiency respectively which are achieved at 1000 cd/m.sup.2.
Finally, EQE1000 denotes the external quantum efficiency at an
operating luminous density of 1000 cd/m.sup.2.
[0200] The data of the OLEDs are summarised in Table 2. Depending
on the substitution pattern, the materials according to the
invention can be employed in different layers and functions. Good
to very good values for efficiency and voltage can be achieved
here.
[0201] According to a preferred embodiment, the compounds are used
as matrix materials for red- and for green-phosphorescent emitters
(Compound Examples 1, 3 and 4). Device examples in this respect are
E1-E4, E7 and E9. E1 and E2 here represent examples in which the
compounds according to the invention are employed as the only
matrix materials, and E3, E4, E7 and E9 represent examples in which
the compounds according to the invention are employed in
combination with a further matrix material (mixed-matrix
systems).
[0202] Furthermore, the compounds according to the invention can
advantageously be employed as hole-transport materials, as shown
with reference to compound Example 2 in device Examples E5 and
E6.
[0203] Again furthermore, the compounds according to the invention
can be employed as electron-transport materials, as shown with
reference to compound Example 1 in device Example E5.
TABLE-US-00003 TABLE 1 Structure of the OLEDs HIL HTL IL EBL EML
HBL ETL EIL Ex. Thickness Thickness Thickness Thickness Thickness
Thickness Thickness Thickness E1 -- SpA1 -- NPB 1:TER1 -- Alq.sub.3
LiF 20 nm 20 nm (85%:15%) 20 nm 1 nm 30 nm E2 -- SpA1 HATCN BPA1
1:TEG1 -- ST2:LiQ -- 70 nm 5 nm 90 nm (90%:10%) 30 nm (50%:50%) 40
nm E3 -- SpA1 HATCN BPA1 ST1:3:TEG1 IC1 ST2:LiQ -- 70 nm 5 nm 90 nm
(30%:60%:10%) 10 nm (50%:50%) 30 nm 30 nm E4 -- SpA1 HATCN BPA1
IC1:3:TEG1 -- ST2:LiQ -- 70 nm 5 nm 90 nm (30%:60%:10%) (50%:50%)
30 nm 40 nm E5 HATCN SpA1 -- 2 M1:D1 -- ST1:LiQ -- 5 nm 140 nm 20
nm (95%:5%) (50%:50%) 20 nm 30 nm E6 -- SpA1 HATCN 2 IC1:TEG1 ST1
ST1:LiQ -- 70 nm 5 nm 90 nm (90%:10%) 10 nm (50%:50%) 30 nm 30 nm
E7 -- SpA1 -- NPB ST1:2:TER1 Alq.sub.3 LiF 20 nm 20 nm
(70%:15%:15%) 20 nm 1 nm 30 nm E8 -- SpA1 HATCN BPA1 ST1:TEG1 -- 1
LiQ 70 nm 5 nm 90 nm (90%:10%) 40 nm 3 nm 30 nm E9 -- SpA1 HATCN
BPA1 IC1:4:TEG1 IC1 ST2:LiQ -- 70 nm 5 nm 90 nm (70%:20%:10%) 10 nm
(50%:50%) 30 nm 30 nm
TABLE-US-00004 TABLE 2 Data of the OLEDs U1000 CE1000 PE1000 EQE
Ex. (V) (cd/A) (lm/W) 1000 CIE x/y E1 4.7 7.7 5.1 12.8% 0.69/0.31
E2 3.7 51 43 14.1% 0.36/0.60 E3 3.6 53 46 14.8% 0.36/0.60 E4 3.8 50
41 13.9% 0.36/0.60 E5 4.2 7.5 5.6 6.1% 0.14/0.15 E6 3.5 55 50 15.3%
0.36/0.60 E7 4.7 6.5 4.3 10.8% 0.39/0.61 E8 4.3 48 35 13.2%
0.36/0.60 E9 3.5 56 50 15.6% 0.37/0.61
TABLE-US-00005 TABLE 3 Structural formulae of the materials for the
OLEDs ##STR00213## HATCN ##STR00214## SpA1 ##STR00215## NPB
##STR00216## BPA1 ##STR00217## Alq.sub.3 ##STR00218## M1
##STR00219## D1 ##STR00220## LiQ ##STR00221## ST1 ##STR00222## ST2
##STR00223## TER1 ##STR00224## TEG1 ##STR00225## IC1 ##STR00226## 1
##STR00227## 2 ##STR00228## 3 ##STR00229## 4
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